The International Telecommunications Union is the UN Body which is responsible for creating agreements among nations with respect to the radio spectrum.
The ITU was founded in Paris, France in 1865 originally as the International Telegraph Union. It changed it’s name in 1932 and in 1947 became a UN agency.
The ITU divides the world up into 3 regions for the sake of international Radio Rules. Most of the USA is in Region 2, but there are some territories in regions 1 and 3. This causes a few small differences in frequency assignments for some U.S. Territories different from those in the 50 U.S. States. So if you’re a ham and you’re operating from a boat or a ship at sea, you’ll have different operating frequency privileges, depending on the ITU region you’re in.
If you get a Ham Radio license, you can use it wherever you are, subject to the authorization of the country you’re in while operating. Most countries allow ham radio operators to operate, although sometimes with more or fewer privileges than us and you often have to give them months of notice beforehand and sometimes pay hefty fees to do so. A few countries have notified the ITU that it objects to FCC-licensed amateur stations exchanging communications. Check with each country before you try to operate there. Of course, in an emergency, you can talk to anyone you can.
When you talk with hams in other countries, the FCC says that you can only discuss Communications incidental to the purposes of the amateur service and remarks of a personal character. I imagine that certain countries don’t want us to discuss politics or certain political philosophies with hams in those countries.
Hams are allowed to put the microphone up to the mouth of a person who isn’t a ham radio operator or connect our radios to telephone lines and make calls on behalf of non hams to allow them to talk to people over ham radio. The ham must ALWAYS be in control of the push-to-talk switch. This is called, 3rd party traffic and can only be done in the USA or among countries that allow it. Not all of them do.
Another popular form of 3rd party traffic is the National Traffic System, a body of rules and procedures adopted internationally as a way to send text messages over ham radio to individuals in countries that allow 3rd party traffic, usually up to 30 words, not unlike a telegram. The NTS has an extensive set of procedures to ensure that messages are copied from one ham to the next to the next all the way to the destination perfectly, without any errors.
FCC Rules, Part 97
Code of Federal Regulations 47 is all about the FCC. Part 97 is all about Ham Radio. The FCC has to Answer to the ITU, an United Nations agency for information and communication technology issues.
Ham Radio is a "...voluntary noncommercial communication service", and provides, "emergency communications". Hams contribute to Advancing skills in the technical and communication phases of the radio art. Hams Help train operators, technicians, and electronics experts and Enhancing international goodwill. (FCC 97.1).
The FCC regulates all radio frequency emissions in United States territories and allows different uses at different frequencies. For example, Part 15 of the FCC rules allows certain unlicensed devices that may emit low powered radio signals on frequencies used by a licensed service.
According to the FCC, a Ham Radio Station is A station in the Amateur Radio Service consisting of the apparatus necessary for carrying on radio communications. The station can be at your home, in your car, whoever you are walking around in US Territories or From any vessel or craft located in international waters and documented or registered in the United States
The FCC allows a person to conduct radio experiments and to communicate with other licensed hams around the world.
But you’re not allowed to broadcast music or earn income or use ham radio in a business. The FCC has other kinds of licenses for those things. You can, however, buy and sell ham equipment when the equipment is normally used in an amateur station and such activity is not conducted on a regular basis, in other words, informal.
You can also charge money when giving a ham radio demonstration during instruction at an education institution.
The main reason why radio has to be licensed is to prevent interference. HarmfulInterference is defined by the FCC as That which seriously degrades, obstructs, or repeatedly interrupts a radio communication service operating in accordance with the Radio Regulations
Ham bands fall into 3 categories of use.
Exclusive to Hams and therefore cannot be interfered with legally, or
Shared with another service, but hams are considered, Primary. This means that whenever a ham is causing interference on this band to operations of another service, the other service just has to put up with it. On the other hand, if the other service interferes with a ham, they have to cease transmission or move to another channel. (I’ll often use the words “Channel” and “Frequency” interchangably; they mean the same thing).
Shared with another service or service(s), but hams are considered secondary. As secondary users, hams are required to not interfere with the other user, up to and including ceasing transmission to prevent such interference. For example, Hams are secondary users on some bands and must always stop transmissions to prevent interference with Radionavigation Service.
willful interference, done on purpose, is never allowed.
In order to resolve conflicts between operators ofrepeater and auxiliary stations, the FCC grants powers to a Frequency Coordinator or Frequency Coordinating Committee to recommend transmit/receive channels and other parameters. A Frequency Coordinator or Frequency Coordinating Committee is chosen by Amateur operators in a local or regional area whose stations are eligible to be auxiliary or repeater stations
If you and another ham operator are interfering with one another, Common courtesy should prevail, because no one has absolute right to an amateur frequency
Ham callsigns in the USA start with A, N, W or K
Callsigns have 1 or 2 letters and then a single digit and then 1, 2 or 3 letters. The FCC grants Special Event callsigns for special events with a single letter and a number and a single letter.
The FCC allows Any licensed amateur to ask for a vanity call sign. A technician class licensees to ask for a vanity call sign (choose your own) but only with 3 letters at the end. Extra class licensees can get a 2x1 or 1x2.
If you have at least 4 members, your club can get a license. The person named as trustee on the club station license grant can ask for a vanity call sign for the club.
You listen to my radio show. You study this guide. You fill out some forms. You show up with your government issued ID and pay your $15. You take and pass a test. You get a license. You can start operating as soon as your operator/station license grant appears in the FCC's Universal Licensing System (ULS) online at fcc.gov.
It lasts 10 years and is renewable.
If you forget to renew your license after 10 years, you still have a 2 year grace period in which to do so. You cannot transmit until the FCC's Universal Licensing System (ULS) online at fcc.gov says your license has been renewed.
If the FCC writes you a letter at the address you gave them and it is returned as undeliverable, they might revoke your station license or suspend your operator license.
There used to be Novice Licenses and Advanced licenses, and Technician Plus licenses but not anymore. The only ham radio licenses now are Technician, General, and Amateur Extra.
The FCC Issues you a callsign. You can look it up in the FCC’s ULS.
When you’re on the air, you say your callsign At least every 10 minutes during and at the end of a communication or a test.
If you are participating in a public event such as a race, you and the other participants can use Tactical call signs instead of your regular ones, but you still have to identify with your regular FCC callsign at the end of each communication and every ten minutes during a communication
According to the FCC, if you are communicating using voice, you must say your callsign in English or using CW
If you are operating away from your normal FCC region, you can give your callsign followed by either “Stroke”, “Slant” or “Shash” and then the region or country code where you are. In CW, use a “/“ character. Ditto if you’ve just upgraded and your upgrade hasn’t yet appeared in the FCC’s ULS. Use either /KT, /AE or /AG.
97.119 (f) If you've upgraded your license and seen it online on the FCC’s ULS but your new license hasn't yet arrived, then you have to say or send your callsign with a suffix, as follows:
Upgrading from Technician, General, or Advanced to Amateur Extra Class: "/AE"
Upgrading from Technician to General Class: "/AG"
Upgrading from Novice to Technical Class: "/KT"
Authorized and prohibited transmission
Indecent or obscene language is prohibited
Messages not in a plane language (with the exception of Satellite Telecommand codes)
Music (with the exception of Spacecraft who have the music on in the background)
During military communications tests, hams can exchange messages with a US military station.
Auxiliary, repeater, or space stations can automatically retransmit the signals of other amateur stations.
Hams may broadcast morse code practice or information bulletins
Broadcasting means Transmissions intended for reception by the general public
In an emergency, when no other means is available, hams can broadcast news, program production, or gather news, but only where such communications directly relate to the immediate safety of human life or protection of property.
You can’t transmit messages in exchange for money. In fact, you can’t ask for any money for just about anything having to do with Ham Radio (Except buying and selling used equipment individually, informally and if you’re part of an educational institution and you’re demonstrating ham radio in a class; they do this for astronauts at NASA).
Operator Privileges and Frequencies
The exact chart that shows on which parts of which bands you can operate which modes using which operator’s license level is called a Band Plan. While the FCC considers the band plan voluntary with respect to modes, it is a rule with respect to operator privileges.
You should not operate too close to the band edges
Radios are not perfect; they can get out of calibration. That’s just a frequency display and not a frequency counter.
Even if your rig is totally on frequency, sometimes, over time, as it warms up, it might drift
Each mode takes up some bandwidth. So even if you’re exactly on the mark, as you talk, your sidebands will get bigger with your speech.
You can use CW on any ham band
You can use SSB or AM on at least some portion of all the amateur bands
Lower sideband for 160, 80 and 40 meters
Upper sideband for 20, 17, 15, 12 and 10 meters
You can use FM on some portion of each band from 28 MHz and up.
Remember that the speed of light and radio waves, 300 million meters per second divided by the wavelength in meters is equal to a frequency somewhere close to the bad.
The 6m band goes from 50 - 54 MHz
The 2m band goes from 144 - 148 MHz. The national calling frequency is 146.52 MHz.
The 1.25m band goes from 222 - 225 MHz, but data only can be used from 219 - 220 MHz
The 70cm band goes from 420 - 450 MHz. The national calling channel is 446.0 MHz.
The 33cm band goes from 902 - 928 MHz
The 23cm band goes from 1240 - 1300 MHz
The 6 meter, 2 meter, and 1.25 meter bands have mode-restricted sub-bands for technician class hams.
Generally, the first 100 KHz of every band is for CW only. For example, 144.0 - 144.1 MHz.
While not exceeding the maximum power permitted on a given band, use the minimum power necessary to carry out the desired communication
Control operator and control types
When the FCC gives you a license, it’s really 2 licenses in 1: a Station license for your equipment and an operator’s license for you. Each set of station equipment, even a handitalkie is licensed as a station license and each person who gets a ham license is a control operator when using such equipment. You can loan your equipment to another ham, even one from outside the country, but they have to only use it within the limits of their operator’s license. Even Repeaters have a control operator — that’s the ham who is listening in case of a problem and can shut the repeater down remotely if needed. No amateur station can transmit without a control operator. Whoever is the station licensee designates the station control operator. The Control Operator and the Station Licensee are equally responsible for proper operation of the station.
T1E02 (D) [97.7(a)]
Who may a station licensee designate to be the control operator of an amateur station?
A. Any U.S. citizen or registered alien
B. Any family member of the station licensee
C. Any person over the age of 18
D. Only a person for whom an amateur operator/primary station license grant appears in the FCC database or who is authorized for alien reciprocal operation
T1E03 (A) [97.103(b)]
Who must designate the station control operator?
A. The station licensee
B. The FCC
C. The frequency coordinator
D. The ITU
Every station has a control point, whether that’s near the transmitter or remote. That’s where the control operator function is performed. The control they’re talking about here is the PTT switch and the ability to override it.
Local control is where the control operator is at the controls of the transmitter directly.
Remote control is where the control operator can control the transmitter from another radio or over the internet or a telephone.
Even repeaters and APRS network digipeaters have a control operator, but since they work under Automatic Control, the control point is always somewhere else such as over the internet or a radio. Contrast that with the Localcontrol or Remote Control which must be used for all other types of transmissions besides those from repeaters, auxiliary stations and satellite transponders.
Unless there’s specific documentation saying otherwise, FCC presume to be the control operator of an amateur station to be The station licensee
An FCC representative can ask to inspect the station or its records at any time.
If an FM receiver (such as the one in a Handitalkie) is just listening to a frequency, we don’t hear any hissing sound because of a radio feature called, “Squelch”. This mutes the speaker until an actual signal is heard, making our hobby more enjoyable. This is called, “Carrier squelch” meaning that a carrier or signal is required to open the receiver’s squelch so you can hear a transmission. The alternative is called “Tone Squelch” where a subaudible tone is inserted along side your voice while you transmit (nobody can hear it except the electronics) so that the receiver listens for that instead. This is called, Continuous Tone Coded Squelch System or CTCSS or sometimes just PL (an old trademark, “Private Line”) or “Buzz”.
Most VHF and UHF operation is on FM (instead of SSB or CW) through repeaters. A repeater is a type of amateur station which simultaneously retransmits the signal of another amateur station on a different channel or channels. We say that it listens on it’s input frequency (the frequency on which you must transmit to use it) and it transmits on it’s output frequency or your receive frequency. Since it is a transmitter, we normally talk about a repeater’s “frequency” (just one) in terms of it’s transmit or your receive frequency.
Nobody can transmit and receive on the same frequency at the same time -they’d just hear themselves. So there are standard offsets in use for each band. The standard offset on 2m isPlus or minus 600 kHz. The standard offseton 70cm is 5 MHz. This is called, “Duplex” operation.
If you are so close to somebody that you can communicate with them directly without using the repeater, normally you would just use a single frequency upon which both of you would exchange transmissions. If you are communicating with somebody else using just 1 frequency for the two of you without a repeater, that is called, “Simplex” operation. The national simplex calling frequency on 2m is 146.52 MHz.
Since a repeater is an automatic system, if it accidentally transmits something which is against FCC rules, the responsible party is whoever made that transmission (assuming they did it on the input frequency). Otherwise, the repeater’s control operator is at fault.
Each repeater is licensed to a control operator whose callsign is sent (usually in morse code) periodically during transmissions through that repeater and that person is responsible for its operation.
Since anybody listening to a repeater can hear everybody who can talk on it easily (unlike on the HF bands where you don’t know if you can hear the other end or not) instead of calling CQ, you canjust announce your callsign. Or say, “WB5QAL Listening”.
Since there are many more repeaters than there are frequencies on which to put them, sometimes, more than one repeater might share the same frequency. Hopefully, this only happens whey they are so far away that nobody can hear both. To choose which one you want to use, a so that you can use 1 tone for 1 repeater and a different CTCSS tone for another repeater and they (hopefully) won’t interfere with one another, even though they’re using the same frequency.
Some older repeaters just require an audio tone burst at the beginning of each transmission. Usually 1750 Hz is the frequency of the tone.
Some newer repeaters use a digital data packet at the beginning of each transmission to allow you to use their repeater, this is called, “Digital Coded Squelch” or DCS. There are a lot more DCS tones than CTCSS tones.
Talking through repeaters is an extremely reliable form of communication but it isn’t perfect.
If you’re driving, you might be right at the edge of a coverage area and you may start Picket Fencing. Wait and try again when you’re in a better location
Occasionally a radio transmitter can become out of adjustment if you bang it hard enough or change temperature too fast it it might be off frequency a little bit and require adjustment.
If your batteries get low, your signal might become distorted, but more than likely, people will hear the first half sentence of everything you say and then nothing afterwards. Charge your batteries.
There is often a 12 or 16 digit keypad on a radio or microphone for sending touch-tones or dual tone multifrequency (DTMF) tones. This is the old standard from AT&T in the 1970s by which phone calls were made from wired telephones after dials became obsolete. Hams use these tones for controlling repeaters, making phone calls over the radio (“Autopatch”) or setting up and taking down links (“IRLP”).
Because it is so reliable, it has been augmented using the internet in various ways. For example, we can use Voice Over IP Protocols (VOIP) to send voice signals received by a repeater to be sent using digital techniques over the internet to another repeater elsewhere. The most common are IRLP and Echolink
Echolink is a way for licensed hams to talk to a particular repeater using a website over the internet.
IRLP or Internet Relay Link Protocal is a system whereby repeaters are connected to the internet and you can use the 12 button keypad on your radio or microphone to “dial” a 4 or 5 digit “node ID” of another specific repeater to which you’d like to be linked and then carry on a conversation on your repeater with somebody on the other repeater. Everyone on both repeaters will overhear, but you’ll be able to converse and, when you’re done, “Hang up” and disconnect the two repeaters. Like a telephone system only your handitalkie is a handset.
Repeater Directories online and on paper list which IRLP nodes are active and working
An amateur radio station, such as an IRLLP capable repeater if it is connected to the internet is called a gateway.
CQ means “Seeking You” or Calling any station
When you first get on the air on HF, you’ll want to try to talk to somebody and most likely, you’ll either listen for somebody else calling CQ or do it yourself.
Make sure you’re in a band where you’re allowed via your license and mode
Listen first to make sure nobody’s using that frequency. Remember that maybe you can hear only 1 side of the conversation
Verbally ask “Is the frequency in use?”
Since repeaters are guarrenteed that if you can get into it, everybody can hear you, we don’t use CQ on a repeater. Mostly, we might say something like, “WB5QAL Listening”.
If you’re trying to reach a specific station or answering somebody’s CQ call or “so-n-so listening”, briefly give the other station's call sign followed by your call sign.
If you’re on HF or if you’re mobile, the FCC recommends that you identify Using a phonetic alphabet to make sure everybody understands your callsign correctly.
To help identify where hams are located, there is an international standard Grid Square Map. A letter-number designator assigned to a geographic location is a “grid square”. My home is in CM89. KPFZ is closer to CM88.
Some hams participate in contests, contacting as many stations as possible during a specified period of time. Because everyone’s going as fast as they can, Send only the minimum information needed for proper identification and the contest exchange. Usually signal strength, location and some brief info about the contest, such as a designation for your equipment or station size.
In morse code, we often use Q signals to indicate specific common phrases
QRM = interference caused by humans; “Somebody is QRMing us - try 5 KHz up”.
QRN = atmospheric interference. “I am experiencing QRN mixed with your signal; I can’t hear you.”
QTH? = Where are you? — QTH = My QTH is Lake County
QSY? = “Please change frequencies to …” ; QSY = “I am changing frequency to …”
QSB? = “Does my signal strength vary?”; QSB = “Your signal strength is going up and down
QRU = “I have nothing for you”; QRU? = “Do you have anything for me?”
QRS = Send more slowly
QRZ? = “Was someone calling me?”
Some hams use computers
For logging contacts and contact information
For sending and/or receiving CW
encoding and decoding digital signals using a Terminal node controller or a sound card to the mic and speaker jacks of the radio
Seeing a graph in real time of the conditions of the band
Programming VHF and UHF radio frequencies from a spreadsheet like application
Seeing a map of APRS stations
In the car
Since most ham equipment runs off of 12vdc and most ham homes have 120vac, it stands to reason that most hams use regulated power supplies. The regulation prevents voltage fluctuations from reaching sensitive circuits which might otherwise make objectionable hum along with your transmissions.
The alternator in your car produces square waves as it turns on and off as it rotates so it produces a lot of RF noise. On the radio, this sounds like high-pitched whine that varies with engine speed
When wiring a rig in the car, try to attach the ground wire At the battery or engine block ground strap
So you have a power supply and radio and mic and key connected perhaps through an amplifier and then an SWR meter and then perhaps through an antenna tuner and finally you’ll want to connect a filter to reduce harmonic emissionsBetween the transmitter and the antenna
Since most ham equipment runs on 12 volts DC, If you don’t have a power supply, you can always power your home ham radio equipment from a 12v automotive or marine battery. Then, drive your car over to the window and use jumper cables to charge it periodically. Connect the battery in parallel with a vehicle's battery and run the engine to increase the voltage high enough to charge both batteries.
Best to use a solid Flat strap for grounding the station to a ground rod
Another popular source of distortion while your listening to an AM or single sideband receiver is hash from power lines. Noise Blanker circuits are designed to mitigate this.
Automatic Gain Control is like an automatic volume control that keeps the signal the same loudness while you’re listening, even as it fades up and down in strength
Just as you can adjust the volume control on your receiver so that it doesn’t distort the sound coming through your speaker, there is also a microphone gain cotrol to adjust the level for different people to be able to talk clearly, some loud, some soft. If it’s turned up too loud, the sound might become distorted on transmit, too.
The best way to hear signals on HF is to set your receiver bandwidth so that it only picks up a big enough chunk of the band to hear the signals you’re looking for. If that’s CW, then 250 or 500 Hz is plenty. For USB and LSB, you can get by with as little as 1.6 kHz, but normally 2400 Hz is considered optimal.
Nowadays, all HF radios have receive and transmit VFO and all VHF and UHF radios have computers controlling a frequency synthesizer so that you can use a keypad or knob to tune any channel and then store it in a memory channel for quick access
When you listen to a single sideband signal, as you turn your VHF knob, you’ll hear part of it then the center (where you’ll hear all of it) and then the other side. Because of this, all modern radios have RIT or Receiver Incremental Tuningto allow you to change your receive frequency but stay transmitting on the same frequency so the person with whom you’re conversing doesn’t chase you down or up the band.
In the old days, you’d have a receiver and a transmitter and they would each have a crystal to specify precisely what frequency upon which you could listen and talk. Later, everybody changed their receivers so that instead of a single crystal controlling a single local oscillator, there would be a variable capacitor to adjust a tuned circuit to change the frequency so that you could turn the VFO knob to hear stations on different frequencies.
Satellite and Radio Control operation
Hams have a few satellites. Ham satellites have Transponders. A Transponder is like a repeater but instead of listening on just one frequency for one person to talk, it listens on a portion of a whole band and repeats the whole band portion and everyone’s conversation on another band. If you have the license privilege to talk on the satellite’s input band, you can use one.
We use satellite tracking programs to see Maps showing the real-time position of the satellite track over the earth and The time, azimuth, and elevation of the start, maximum altitude, and end of a pass and The apparent frequency of the satellite transmission, including effects of Doppler shift.
time, azimuth and elevation
LEO - Low Earth Orbiting Satellites are so close that they move much faster and can sometimes be seen twice or more often in 1 day.
Geosynchronous - An orbit around Earth whose orbital period is equal to a sidereal day (23 hours, 56 minutes), irrespective of its inclination.
- A person on a point on Earth, will see a satellite in this orbit in the same place in the sky at the same time of the day, everyday.
Geostationary - A geosynchronous orbit around Earth at 35,786 km above the equator, so that it remains stationary as seen from Earth.
- A person on any point on Earth, will see a satellite in this orbit stationary w.r.t his position, just like a star in the sky.
Doppler shift is An observed change in signal frequency caused by a change in distance between the satellite and the earth station. Think of a train whistle, changing its pitch as it comes closer and then goes farther away.
The Keplerian Elements are a set of numbers which allow satellite tracking programs (or really patient humans) to calculate a satellite's position in space. Named after (wikipedia) Johannes Kepler, (1571-1630), German astronomer who discovered what we call the three major laws of planetary motion.
You should only use enough power to complete the contact
Many astronauts are hams. The Ham license training is an optional part of Astronaut training. So the ISS often has hams aboard.
If you have a technician license, and they’re available, you can talk with them.
If you’re talking to somebody in a manned spacecraft, they’re allowed to have music on incidental to an authorized retransmission of manned spacecraft communications
Satellites often transmit information about themselves using a beacon, which is just a fancy word for a transmitter that sends out some kind of data that the inventor of the beacon thought might be useful or interesting to somebody. The most popular kind of data to send is telemetry. According to the FCC, Telemetry is defined as a one-way transmission of measurements at a distance from the measuring instrument
And, while we’re on the subject, A one-way transmission to initiate, modify or terminate functions of a device at a distance is called Telecommand. These are required for satellite operating, in case nobody is there to stop the transmitter. It's okay to transmit one way, not expecting a reply.
Telecommand is also used to control radio-controlled vehicles on ham frequencies up to a maximum transmit power of 1 watt. You don’t have to identify. Instead, A label indicating the licensee's name, call sign and address must be affixed to the transmitter.
Telecommands may be encrypted to hide their contents. But that is the only situation in which hams are allowed to have secret communications. All others must be in plane language.
Most satellites have more than one transponder. We talk about them by using terminology such as U/V to mean a UHF uplink and a VHF downlink. That is, in order for you to talk though a satellite transponder operating in U/V mode, you must transmit your SSB or CW or FM or FM packet digital signal on UHF (70cm) and receive the satellite’s transmissions of your signal and that of whoever responds to you on VHF, or 2 meters.
Satellites have a different kind of noise than normal radio communications. Rotation of the satellite and its antennas causes spin fading.
There are digital satellites which only work for FM Packet Radio
Radio Amateur Civil Emergency Service and Amateur Radio Emergency Service are two separate organizations that may provide communications during emergencies
ARES is a group of Licensed amateurs who have voluntarily registered their qualifications and equipment for communications duty in the public service
A radio service using amateur frequencies for emergency management or civil defense communications
A radio service using amateur stations for emergency management or civil defense communications
An emergency service using amateur operators certified by a civil defense organization as being enrolled in that organization
During emergencies, one station will act as a net control operator on a given frequency or channel. Since almost all of our radio equipment is designed to work in half-duplex operation as opposed to full duplex, it is necessary to know who is supposed to begin talking when somebody else stops. It is always the net control operator who gets to speak and ask everybody else to answer him or her.
Therefore, when an emergency occurs and you’re at a radio, find a local net and listen for the net control operator to ask for checkins. Follow the instructions (usually by saying your callsign when they ask for checkins and letting them know your location or whatever information they ask you for. Then, remain on frequency without transmitting until asked to do so by the net control station.
IN an emergency, an accepted practice to get the immediate attention of a net control station is to begin your transmission by saying "Priority" or "Emergency" followed by your call sign.
“Priority” means having to do with the safety of property of the safety of people’s or animals lives which are not in immediate danger.
“Emergency” is a word only used to refer to an immediate life-threatening situation
In an actual emergency, you can transmit wherever you need to to resolve the emergency, but only if necessary in situations involving the immediate safety of human life or protection of property
To further the FCC’s aim that ham radio operators provide public service, there has been a culture in ham radio of playing the game of telephone for passing messages called, Radiograms on behalf of non-hams to aid during disasters and public events. This is much less prevalent since the advent of cellular phones, but still regularly practiced.
Messages are passed always for free by Hams on behalf of anybody who lives in countries that accept 3rd party traffic to and from the United States. Messages may generally be up to 25 or 30 words long and must be of a personal nature, not related to business or financial transactions.
Obviously the goal is to pass messages exactly as they were received.
The ARRL’s National Traffic System Radiogram format.
Messages are in a standard format which includes a preamble with The information needed to track the message as it passes through the amateur radio traffic handling system followed by the contents of the message itself, usually fewer than 30 words long with only question marks and periods and commas for punctuation, rather like a telegram. Message usually arrive within a few days to a week. This is a free service that hams perform to keep in practice.
When Passing messages via voice including proper names or unusual words, such words and terms should be spelled out using a standard phonetic alphabet
Each subculture has a different set of standard words used for describing letters of the alphabet. Using words like this is called, “Phonetics” because you’re are using Phonemes to disambiguate the letters.
For example, Ham Radio Operators use:
Whereas aircraft use
While police agencies often use
The Preamble of a radiogram always begins with sequence number kept by the ham who is first writing -or originating- the message. Usually, since the message already includes a date, this can start at 1 for each month or year, depending on how many messages each ham creates each month or year. The purpose of this number is so that when there are replies or Service Return Messages sent back to the originating station, they can refer to this number and it will make it easy for the originating station to figure out which one it was.
The next part of the preamble of a radiogram contains a single letter called the PRECEDENCE. The Precedence of the Message determines what order the messages will be handled. Most of the time all messages are handled on every net session. The following four precedences are used in ascending order of priority:
ROUTINE (R on CW) 99.99% of all messages have this precedence. These messages will be handled last.
WELFARE (W on CW) This message is either an inquiry to the health and welfare of an individual in a disaster area or a report of the health and welfare of an individual. These messages will be handled before ROUTINE traffic.
PRIORITY (P on CW) These are messages have specific time limits. They are also for Official messages, not covered in the EMERGENCY category. This traffic will be handled before WELFARE or ROUTINE.
EMERGENCY (EMERGENCY spelled out on CW) Any message having life and death urgency to any person or group of persons, which is transmitted by Amateur Radio in the absence of regular communication facilities. When in doubt, do NOT use this precedence. This traffic will be handle first and immediately.
The next part of the preamble to a radiogram are the HANDLING INSTRUCTIONS. Handling Instructions are sometimes used to tell the various stations along the way, what the desires of the originating station are. If not needed, it is best not to use. On voice: the sending station would say, "HANDLING INSTRUCTIONS (*)", as explained below. On CW: Send the letters below:
HX A (Followed by a number) Collect land line (telephone) delivery authorized by the by addressee within ... miles. (If no number, authorization is unlimited).
HX B (Followed by a number) Cancel message if not delivered within ... hours of filing time and service originating station.
HX C Report the time and date of delivery to originating station. That is, compose a Service Return message to the originating station referring to their message number on such-n-such a date and say the date and time of message delivery.
HX D Report to the originating station the identity of the station from which you received, plus time and date. Report the identity of the station to which it was relayed, plus time and date, or if delivered report time and date of delivery.
HX E Delivering station gets a reply from the addressee, and originates a message back.
HX F (Followed by number) Hold delivery until the date specified after the F. That is, HXF 4/17/63, or whenever.
HX G Delivery by mail or land line toll call not required. If toll or other expense involved, cancel message and service originating station.
Note that you can combine several of these together for one message. For example, HXABDF.
The next bit of information in a radiogram preamble is the Originating Station Callsign. This is the call sign of the Ham Radio operator generating (writing) this message. This call sign, along with the message number, serve as the "serial number" of this message. Any future reference to this message would be: "Number nn of CALL nnXnnn".
The next part of the preamble of each message is a check. This refers to the counted number of words and punctuation marks in the body of the message itself, not including the preamble. The check value refers to words or groups of letters and numbers surrounded by spaces, not including punctuation. The only punctuation allowed within radiograms are:
At the end of each sentence, the letter X is used instead of a period. The X is a word by itself.
If you have to send numbers with decimal points, the letter R is used in place of the period within a number. For example, within a radiogram, 3R1415 is how you would send 3.1415.
A question mark or comma is allowed.
The preamble continues with the Place or Origin. This is the location of the original person who wanted to send the message, not necessarily that of the Ham Radio operator originating the message. That is, if I write a message on your behalf, I, as the ham, am the originating station and my callsign goes in that part of the preamble, but the location where you are when we send the message goes in the place of origin.
Time Filed is optional but whether it is there or not, a Date Filed is mandatory.
The last standard piece of information within the preamble is the Address which begins with the Recipient’s name (and callsign, if that person is a ham operator). This looks like a regular address on the outside of a letter, but wherever you would get to the end of a line and start a new line, insert a “/“ forward slash character instead. (There is no backslash character in morse code, so none can appear within radiograms).
Optionally, at the end of the preamble, there might be an OP NOTE or operator’s note to say how to reach the originating station or originating person, if needed.
Next comes the text of the message, organized into words or groups of letters and numbers separated by spaces. Note that X is used to conclude each sentence and is a word, all by itself.
The body of a radiogram will often include one or more of a number of standard numbered radiogram messages, defined by the American Radio Relay League and the National Traffic System followed by simple phrases to specify details.
If you charge or use up a lead-acid storage battery too fast, it can overheat and give off flammable gas or explode
If you Short the terminals, it can cause burns, fire, or an explosion
Electrical current flowing through a human body
physically heats tissue, like a microwave oven heats meat
disrupts the electrical functioning of cells
causes involuntary muscle contractions
The electricity coming into your home starts out as 3 phase 240 volt 60 cycle AC
Red and Black are hot
White is neutral - white to red and white to black are 120 vac
Green is ground
Fuses and circuit breakers exist to break a circuit rather than heat up wires beyond their capacity.
For example, if you have a circuit which requires a 5 amp fuse, that means that the wires in that circuit and other components can only accommodate up to 5 (or, more likely, 4 or less) amps. If you change that 5 amp fuse for a 20 amp fuse, that means that if a component fails and you accidentally end up with 19 amps flowing through the circuit, then those components the fuses is there to protect will fail instead of the fuse. If one of those components is a wire passing too close to something flammable, than that wire will heat up and possibly start a fire.
Guard against electrical shocks at your ham station:
Use 3 wire cords and plugs for all AC equipment and connect the ground wire to chassis ground
Connect all AC powered equipment in your station to a common ground
Plug it all into a GFCI outlet. “A GFCI is much more subtle. When you look at a normal 120-volt outlet in the United States, there are two vertical slots and then a round hole centered below them. The left slot is slightly larger than the right. The left slot is called "neutral," the right slot is called "hot" and the hole below them is called "ground." If an appliance is working properly, all electricity that the appliance uses will flow from hot to neutral. A GFCI monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit. It is able to sense a mismatch as small as 4 or 5 milliamps, and it can react as quickly as one-thirtieth of a second.
So let's say you are outside with your power drill and it is raining. You are standing on the ground, and since the drill is wet there is a path from the hot wire inside the drill through you to ground (see How Power Distribution Grids Work for details on grounding). If electricity flows from hot to ground through you, it could be fatal. The GFCI can sense the current flowing through you because not all of the current is flowing from hot to neutral as it expects -- some of it is flowing through you to ground. As soon as the GFCI senses that, it trips the circuit and cuts off the electricity.” http://home.howstuffworks.com/question117.htm
According to a 1999 study by the American Society of Home Inspectors, 21% of GFCI circuit breakers and 19% of GFCI receptacles inspected didn't provide protection, leaving the energized circuit unprotected. In most cases, damage to the internal transient voltage surge protectors (metal-oxide varistors) that protect the GFCI sensing circuit were responsible for the failures of the protection devices. In areas of high lightning activity, such as southwest Florida, the failure rate for GFCI circuit breakers and receptacles was over 50%!
GFCIs will also fail if you wire them improperly. The most important thing to remember when wiring them is to connect the wire originating at the breaker to the line side of the GFCI and the wire connecting downstream to the load side of the device. The GFCI terminals are clearly marked “Line” and “Load.”.http://ecmweb.com/basics/how-gfcis-work
Mitigate lightning strikes on your antennas by grounding through lightning protectors such as gas-discharge type and ground all of them to the earth and each other.
When you build equipment which plugs into the wall (such as a power supply) always include a fuse or circuit breaker in series with the AC hot conductor
Remember that, if you build a power supply, it might have very big capacitors which store electrical energy, even when the power is removed it can shock you.
When working on a tower with others, always wear a hard hat and safety glasses because the FCC rules say you should. Safety glasses around a tower might be useful if you’re welding or looking up when somebody drops a screw, …ditto hard hat
Even climbing a tower, the FCC wants you to wear safety glasses with your climbing harness.
They also insist that you never do it alone, even if it’s just 20 feet up.
DO identify all the overhead electrical wires and place your mast or tower and antenna system so that, if it fell, it wouldn’t fall within 10 feet of the wires. Duh.
DO use a gin pole to lift tower sections because it is the easiest way to put up a tower if you don’t own a giant crane
DO NOT climb a telescoping or crank-up tower unless it is all the way retracted.
DO use a separate 8 ft ground rod for each leg of the tower and bond them to each other also. DON’T make sharp bends in the wires. DO Ensure that connections are short and direct
DO NOT use a utility pole to hold up your antenna because you might be a moron and place it in such a fashion as to accidentally touch high voltage wires if it were to blow away or break or fall.
Tower Grounding requirements are specified by local electrical codes
Electricity and Electronics
The Metric System, Powers of 10
The metric system is a different set of units for measuring things than most Americans use. An important part of the metric system is a set of word prefixes which are used to denote either multiply by 10 a number of times (3, 6, 9, etc) or divide by 10 so many times. Here are a few popular metric prefixes
Tera — one trillion. A terabyte = one trillion bytes.
Giga — one billion. A gigahertz = one billion hertz. More on that later.
Mega — one million. A megohm = one million ohms. More on that later.
Kilo — one thousand times. A kilogram = one thousand grams
Milli — one thousandth of. A millivolt = one one-thousandth of a volt. 1000 millivolts = 1 volt. More on that later.
Micro — one millionth of. A microwatt = one millionth of a watt. 1,000,000 microwaves = 1 watt. More on that later.
Nano — one billionth of. A nanofarad = one billionth of a farad. 1 billion nanofarad = 1 farad. More on that later.
Pico — one trillionth of. A picoliter = one trillionth of a liter. A trillion picoliters makes one liter.
There are several different kinds of units to which you will become exposed reading this document which lend themselves very well to being expressed using these prefixes as a shorthand to note how much of something there is.
Insulators, Conductors and Semiconductors
So the world is composed of matter and energy. Matter is the What (Nouns) and energy is the How (Verbs).
Energy comes is 8 popular flavors:
Mechanical or Kinetic -- movement, motion, vibration, sound waves
Heat or Thermal -- actually, this is vibration or micromechanical energy
Gravitational -- we don't float away, ocean tides, spinning planets
(Potential) -- Stored; a book on shelf hasn't fallen yet (gravity), batteries (Chemical), energy which is available, but not yet used. I include it here only for completeness; whenever you read about energy, they'll say there are 2 kinds; Kinetic and Potential. I was always confused by that, myself. That's why I'm listing it here. All those other kinds of energy are actually happening; potential energy is waiting to happen.
For our purposes, matter is decided into these 3 general categories
Things which can easily conduct electricity which we call conductors. A few popular conductors include:
Things which quite poorly conduct electricity which we call insulators. Here are some materials which have good electrical insulation properties:
Things which sometimes, under the right conditions, conduct electricity which we call, semi-conductors. These are the materials out of which most electrical components are manufactured. They are responsible for all electronics
Naturally, there are many other substances in the world which conduct electricity to varying degrees. For example, human bodies will conduct electricity when the amount of voltage exceeds 50 - 75 volts. More on that later.
So what is electricity?
Humans believe that all matter is composed of 1 or more elements.
Depending on Temperature, some elements are gas, liquid or solid. These are called that states of matter.
There’s a fourth state of matter called, “Plasma” which is a kind of excited static electricity, which we won’t discuss because I don’t understand it well enough.
An element is a single kind of stuff composed of all the same configuration of atoms. There are fewer than 150 different elements.
An atom is thought to be the smallest single unit of matter Atoms can combine with the same kind of other atoms to make substances as well as different kinds of atoms to make molecules. For example, hydrogen and oxygen are elements which become a gas at room temperature. But when they combine, 2 hydrogen atoms attach quite firmly to 1 oxygen atom to make water. That is what the ‘2’ means in H2O.
An atom is composed of Neutrons and Protons which are bundled together in a Nucleus and Electrons which are thought to orbit the nucleus.
Electrons and protons are the basic building blocks of electrical charge. Electrons are negative charge and protons have positive charge. Neutrons are called that because they’re neutral and have no electrical charge.
Different elements contain different numbers of protons, neutrons and electrons.
It is important to remember that -although we call them protons, neutrons and electrons, really, they’re all so small that we have no idea if they’re all little “things” or particles or if they’re just stuff. Electrons, in particular, are many thousands of times smaller than protons and neutrons and they often behave as though they’re just some kind of energy wave rather than individual things. But, we call them individual things because they behave like that at other times.
Electrons often jump from one atom to another. An atom with too few electrons is said to be a positive ion and an atom with too few electrons is said to be a negative ion. An ion is just an atom with an inappropriate number of electrons.
An Insulator is a material in which the electrons are tightly held by their nuclei and so they don’t move around and make ions. A conductor, on the other hand, is a material in which electrons will easily and readily move around within the material to make either positively or negatively charged ions. Semiconductors are more complicated. More on that later.
One of the popular reasons for calling Electrons, Neutrons and Protons, “Particles” is that they appear always to only exist in discrete quantities. That is, nobody has ever noticed 4-½ electrons; only 3 or 4 (or however many). For this reason, we will talk from now on about electrons and neutrons and protons as though they are individual particles, but please remember that they do not always exhibit the characteristics of physical particles, maybe because they’re really small or maybe because they interact with each other and the rest of the world is ways that we don’t yet understand.
Electricity is the presence of electrical charge. In static electricity, the ions and electrons of electrical charge are in a giant disorganized chaotic mess with no order.
Electrical charges come in two flavors. The electrons are called a negative polarity and the positively charged ions are considered therefore to have a positive polarity. Like charges repel. Different charges attract.
Static electricity has few uses because of its inherent disorder. But we can make the electric charge move in one specific direction, though wires from a source of electricity, through wires, to a load and through more wires and back to the source. We will call this, current electricity.
In current electricity, a bunch of electrons flow in one direction and a bunch of positive ions or “holes” where the electrons used to be flows in the opposite direction. We arbitrarily say that the electrons flow towards the negative and we say that the destination of the “holes” is the positive side of a circuit.
When electricity flows like this, continuing in one direction for a sustained period of time (say, more than 1 second) we call this direct current. More on this later.
6.24 x 10 to the 18th power of electrons = 6 240 000 000 000 000 000 electrons is equal to one coulomb.
1 coulomb of electrons passing by one point on the wire in 1 second is considered to be one ampere of current. A handy way to remember this is to think of current as the flow rate of electricity
The amount of electric charge contained in a given area at one time is a characteristic of electromotive force (EMF) which is usually called, Voltage and is -not coincidentally- measured in Volts.
Most wires (unless they are either super cooled or made out of extraordinarily exotic materials called superconductors) don’t pass along all the electrons you try to put through them. A few are lost and their electricity is converted to heat. The amount to which this happens is called, resistance and is measured in units called, “Ohms” and symbolized using the greek letter omega. Zero ohms of resistance would be a perfect conductor and infinite ohms of resistance would be a perfect insulator. Nothing is perfect.
Power is measured in Watts. 746 watts of power = 1 horsepower of force and yes, electric motors whose power is usually specified in horsepower will draw the same amount of electricity that you would expect from their power rating. For instance, a 1 horsepower motor will require 746 watts of electricity. If it says it should be connected to 12 volts, then you can figure out using ohm’s law how much current it needs and therefore, how thick the wires are that you need to use it with. See the section on “Ohm’s Law” for details.
There is a relationship between amps, ohms, volts and watts of power. That relationship is called, ‘Ohm’s Law’. Ohm’s law is composed of these 2 equations:
E = IR, Voltage (E) = Current (I) multiplied by Resistance in Ohms (R). So E / I = R and E / R = I also.
P = IE, Power in Watts = Current (I) multiplied by Voltage in Volts (E). So P / E = I and P / I = E.
Ohm’s law explains the relationship between volts and amps and ohms and watts at any single point within an electrical circuit. The voltage across any two points in a circuit divided by the resistance across those points will tell you the current flowing through the circuit between those points.
As you might imagine, you can measure Voltage directly in a circuit using a device called a voltmeter. You can measure current using a device called an ammeter. Resistance is measured using an ohmmeter.
Usually, these three devices are combined into one piece of inexpensive test equipment called a multimeter. While there is a device called a wattmeter, usually it is only used for Radio Frequency applications, not the direct current we’ve so far been discussing. More on that later.
Since voltage is a potential force, you can measure it whether it is being used or not. So to measure voltage, put the probes of the voltmeter in parallel with the circuit to be tested. That is, across it. Polarity is important. Plus to plus, minus to minus.
An ammeter, on the other hand, needs to measure the flow rate of the current in the circuit as it is being consumed so it wouldn’t make any sense to measure current the way we measure voltage. To measure current, the ammeter probes must be put in series in the circuit while it is running. That is, if you have a simple circuit with a battery and a light bulb, you would connect one side of the battery to one side of the ammeter and connect the other side of the ammeter to one side of the light and connect the other side of the light to the other side of the battery. This is called putting the ammeter in series in the circuit.
An ohmmeter will measure the electrical resistance across one part of a circuit but beware, ensure that the circuit is not powered to protect the ohmmeter. If you accidentally attempt to measure voltage when using the resistance setting, you might damage the multimeter.
The Electromagnetic Spectrum and Alternating Current
Wavelength and Frequency and the speed of light and radio waves
Impedance and Resistance and Q
What is meant by the term impedance?
A. It is a measure of the opposition to AC current flow in a circuit
B. It is the inverse of resistance
C. It is a measure of the Q or Quality Factor of a component
D. It is a measure of the power handling capability of a component
What are the units of impedance?
What term describes the number of times per second that an alternating current reverses direction?
A. Pulse rate
What is the name for a current that reverses direction on a regular basis?
A. Alternating current
B. Direct current
C. Circular current
D. Vertical current
What is the name for a current that flows only in one direction?
A. Alternating current
B. Direct current
C. Normal current
D. Smooth current
Passive Electrical Components
Resistors, Variable Resistors, Rheostats and Potentiometers
What electrical component is used to oppose the flow of current in a DC circuit?
What type of component is often used as an adjustable volume control?
A. Fixed resistor
B. Power resistor
What electrical parameter is controlled by a potentiometer?
D. Field strength
What electrical component is used to connect or disconnect electrical circuits?
D. All of these choices are correct
Which of the following can be used to display signal strength on a numeric scale?
series and parallel
Which of the following battery types is rechargeable?
A. Nickel-metal hydride
C. Lead-acid gel-cell
D. All of these choices are correct
Which of the following battery types is not rechargeable?
Farads and Microfarads and picofarads
What is probably happening when an ohmmeter, connected across an unpowered circuit, initially indicates a low resistance and then shows increasing resistance with time?
A. The ohmmeter is defective
B. The circuit contains a large capacitor
C. The circuit contains a large inductor
D. The circuit is a relaxation oscillator
What electrical component stores energy in an electric field?
What type of electrical component consists of two or more conductive surfaces separated by an insulator?
What is the ability to store energy in an electric field called?
What is the basic unit of capacitance?
A. The farad
B. The ohm
C. The volt
D. The henry
Henrys of Inductance
Relays and Solonoids
What best describes a relay?
A. A switch controlled by an electromagnet
B. A current controlled amplifier
C. An optical sensor
D. A pass transistor
What type of electrical component stores energy in a magnetic field?
What electrical component is usually composed of a coil of wire?
What is the ability to store energy in a magnetic field called?
What is the basic unit of inductance?
A. The coulomb
B. The farad
C. The henry
D. The ohm
Impedance vs Resistance
Reactance and Impedance
Capacitive and Inductive Reactance
Impedance and Frequency
Eli the Ice man
Hi pass and lo pass filters
Tuned Circuits and Filters
Which of the following is used together with an inductor to make a tuned circuit?
B. Zener diode
What is a simple resonant or tuned circuit?
A. An inductor and a capacitor connected in series or parallel to form a filter
B. A type of voltage regulator
C. A resistor circuit used for reducing standing wave ratio
D. A circuit designed to provide high fidelity audio
Active Electrical Components
Diodes, light-emitting and otherwise
What electronic component allows current to flow in only one direction?
D. Driven Element
How is the cathode lead of a semiconductor diode usually identified?
A. With the word cathode
B. With a stripe
C. With the letter C
D. All of these choices are correct
What does the abbreviation LED stand for?
A. Low Emission Diode
B. Light Emitting Diode
C. Liquid Emission Detector
D. Long Echo Delay
What are the names of the two electrodes of a diode?
A. Plus and minus
B. Source and drain
C. Anode and cathode
D. Gate and base
Which of the following is commonly used as a visual indicator?
C. Zener diode
D. Bipolar transistor
Transistors, field effect and otherwise
What class of electronic components is capable of using a voltage or current signal to control current flow?
Which of these components can be used as an electronic switch or amplifier?
Which of the following components can be made of three layers of semiconductor material?
D. Pentagrid converter
Which of the following electronic components can amplify signals?
B. Variable resistor
C. Electrolytic capacitor
D. Multi-cell battery
What does the abbreviation FET stand for?
A. Field Effect Transistor
B. Fast Electron Transistor
C. Free Electron Transition
D. Field Emission Thickness
What are the three electrodes of a PNP or NPN transistor?
A. Emitter, base, and collector
B. Source, gate, and drain
C. Cathode, grid, and plate
D. Cathode, drift cavity, and collector
What at are the three electrodes of a field effect transistor?
A. Emitter, base, and collector
B. Source, gate, and drain
C. Cathode, grid, and plate
D. Cathode, gate, and anode
What is the term that describes a transistor's ability to amplify a signal?
B. Forward resistance
C. Forward voltage drop
D. On resistance
What is the name of a device that combines several semiconductors and other components into one package?
B. Multi-pole relay
C. Integrated circuit
Electrical Schematics or Schematic Diagrams are a kind of visual shorthand to describe how to hook up the components of electrical circuits to one another to make something you want. A Schematic is a standardized representations of components in an electrical wiring diagram.
The way components are interconnected is accurately represented in electrical circuit schematic diagrams
The most basic element of a schematic is a straight line, signifying a wire connecting 2 or more components (one at either end).
Most of the time on schematics, wires (and therefore, most components) with either be oriented horizontally or verticalling on the page, not diagonally.
When two lines cross (always at right angles) they are either connected to one another or not. To show them connected, fill in a small circle where they meet. To show them as not connected, one or the other “hops over” using a small half-circle (about the size of the filled in circle to show them connected, although sometimes a bit bigger). That is, one line is going straight through while the other stops just before it, the perimeter of half of a circle connects it to where it continues past the other line.
Since we all know that electrical circuits require two wires to do anything, this is often abbreviated in DC circuits. Ether an open circle or a triangle is used to signify that this point connects to the positive input voltage; you can tell because it’ll usually say, “+V” next to it. A triangle pointing down or a horizontal line connected from above with short lines coming off the bottom of it at an angle (all of them the same angle) signifying, “Ground” or the minus of the DC voltage which is almost always understood to be connected to the metal chassis box housing the circuit or the electrical ground connected to a ground wire buried in the actual ground somewhere.
The symbols on an electrical circuit schematic diagram representElectrical components
Components on schematics are almost always labelled using a letter or two from the list below to show what kind of component it is followed by a sequence number, beginning at 1 for how many there are.
A1..An — Antenna
B1..Bn — Batteries
C1..Cn — Capacitors and variable Capacitors
D1..Dn — Diodes, including LEDs
F1..Fn — Fuses
IC1..ICn — Integrated Circuit
J1..Jn — Junction or connection point
K1..Kn — Relay
L1..Ln — Incandescent Lights
M1..Mn — Motors (usually DC) or Meters
P1..Pn — Plug (usually AC)
Q1..Qn — Transistor
R1..Rn — Resistor
S1..Sn — Switch or button
T1..Tn — Transformer
U1..Un — also integrated circults
V1..Vn — Viractor Diodes
Y1..Yn — pizzoelectric Crystal
Z1..Zn — Zener Diode
Here are the schematic symbols for a few popular electronic components
AC voltage source
Variable Resistors, Rheastats, Potentiometers
Capacitors and Variable Capacitors
Inductors and Transformers
Electronic Construction Techniques
The first step to make an electronic circuit is to draw a schematic diagram of how you expect to hook up components together. You can draw it on paper or there are many computer programs that allow you to use computer drawing tools to place standard electrical component symbols onto your schematic..
The first time you begin to work with electronics, the easiest by far way to do so is by using a breadboard. These are small white flat plastic things with a grid of holes in them into which you can literally shove the solid wires coming out of electrical components. In the grid, certain holes are connected together so that you can “plug” components into it and have them be connected together to make a circuit to try out what you want before permanently attaching components to one another.
Once you have made your circuit using a breadboard and you are satisfied with its operation, you can solder the components to a protoboard. A protoboard is a circuit board onto which you can solder components and wires and solder bridges to connect up everything the way you want.
How to Solder
Soldering is a skill in which you use an electric soldering iron to melt metallic solder in order to make semipermanent connections between components or wires. The electric soldering iron heats up to between 300 and 800 degrees Fahrenheit which is hot enough to melt the solder.
Before beginning, clean the surfaces to be soldered using an alcohol based cleaner, if they aren’t already clean.
Then, either use flux core solder or apply some flux (or both). Many people like to use Rosin-core solder as the rosin is a type of Flux. At least according to FCC technician license question pool question number T7D08, Rosin-core solder is best for radio and electronic use
Then, heat up the wires or component wires to be soldered while feeding the solder onto the wire until it melts. The solder will flow around wherever the flux was applied.
If, afterwards, you end up with A grainy or dull surface, you have made a cold solder joint. This means there wasn’t enough heat coming from the things you want to connect for the solder to adhere to them and you have to do it over again.
Clean up the excess flux.
Wash, rinse, repeat.
Normal electronic circuits are built using a custom designed (for each circuit) printed circuit board. There are many manufacturing companies who will be very happy to take the design files produced automatically by your computerized circuit schematic drawing program and make you a printed circuit board specifically for that schematic.
In fact, it is relatively easy to make your own printed circuit boards at home using chemicals and transparency plastic you can buy which will work in your laser printer. Instructions are all over the internet.
Radio Building Blocks
Decibels and S-Units
What is the approximate amount of change, measured in decibels (dB), of a power increase from 5 watts to 10 watts?
A. 2 dB
B. 3 dB
C. 5 dB
D. 10 dB
What is the approximate amount of change, measured in decibels (dB), of a power decrease from 12 watts to 3 watts?
A. -1 dB
B. -3 dB
C. -6 dB
D. -9 dB
What is the approximate amount of change, measured in decibels (dB), of a power increase from 20 watts to 200 watts?
A. 10 dB
B. 12 dB
C. 18 dB
D. 28 dB
Modulator, Gain, Bandwidth, Sensitivity, Selectivity
Modulation and Demodulation
AM and SSB
FSK and AFSK
PSK31, Pastor, HF Digital Modes
JT65, VHF/UHF Digital Modes
How do Radios work
RF & Radio Terminology
When we’re discussing radios, we talk about 2 vernal varieties of AC signals. Audio Frequency and Radio frequency signals. Audio frequency or AF signals are AC voltages whose frequency could drive a speaker or could be driven by microphones as they are within the spectrum of audio that humans can hear. Radio Frequency signals are those which can be fed to or from an antenna. All types of radio frequency signals are considered, “RF”.
Since any wire can act as an antenna, wires carrying RF signals inside radios, particularly those signals whose frequency is high enough that their wavelength could make those wires good antennas at that frequency are often shielded to prevent such emissions. Since a wire can also receive a signal at frequencies whose wavelength is related to the length of that wire, wires are also often shielded to prevent coupling of unwanted signals.
For example, a broadcast AM or FM radio receiver might unintentionally receive an amateur radio transmission if it was designed with insufficient filters to to reject strong signals outside the AM or FM band.
Modern radio transmitters and receivers operate using similar principles.
An RF signal comes in from a receive antenna and is immediately amplified and then mixed with a signal of lower frequency. When you mix signals, you get 4 signals out; the two original signals and their sum and difference. A receiver filters out all but the difference and then amplifies that signal in one or more intermediate stages (collectively called the IF or Intermediate Frequency sections of the receiver) and then mixes again with an even lower frequency so it can decode or demodulate the audio signal from the carrier signal, send it to an amplifier and subsequently, speakers or headphones.
A transmitter is remarkably similar. Audio from a microphone is amplified and then used to modulate a signal at a higher frequency -often 10.7 MHz is the IF of VHF and UHF transmitters- and then mixed again with the local oscillator or variable frequency oscillator or frequency synthesizer to get to the desired transmit frequency and then subsequently sent through a feed line to a transmitting antenna.
A transceiver contains a transmitter and a receiver and usually some kind of transmit-receive relay to switch the antenna between them when you press the PTT switch on the microphone.
Low power transceivers, such as a handheld transceiver are sometimes connected to An external RF power amplifier to increases their low-power output
Just as with external power amplifiers on transmit, an RF preamplifier is sometimes installedbetween the antenna and receiver to make up for a feed line which might be loosing signals because it is too long. In this case, the RF preamplifier must be installed close to the antenna to do the most good.
AM and SSB transmitters modulate a carrier with your voice. FM transmitters modulate by deviating the transmitted signal as you speak. If you talk too loud or too close to the microphone, you run the risk of making too much voltage in the modulation or deviation section of your transmitter. This is called over-modulation on AM and SSB or over-deviatingon FM. Just talk softer or Talk farther away from the microphone to fix this kind of distortion.
Most radios and many other devices such as computers are not designed to be powered directly from the 120 VAC power available at outlets in our homes. Instead, it is usually much easier and less expensive to design equipment to run off of a lower voltage with direct current DC instead of alternating current (AC).
There are two popular ways that power supplies are designed. They are called, “Linear” and “Switching”.
A switching power supply uses a switching transistor to convert the AC sine wave to a square wave which is then rectified. While this is usually much smaller, lighter and more efficient than linear power supplies, the square wave signal puts out a lot of radio frequency interference (RFI) so its use is often discouraged for ham radio applications.
A linear power supply uses a transformer whose primary windings are connected to the 120 VAC source, hopefully through a circuit breaker or fuse to prevent short circuit conditions such as current overload or component failure from creating fires or damaging more expensive components.
The secondary windings of the transformer in a linear power supply are then converted directly from AC to DC using either 1, 2 or 4 diodes or rectifiers.
After rectification, the DC is still rippling quite strongly and must be evened out, usually using large electrolytic capacitors. Then a voltage regulator is usually employed to control the amount of voltage output by the power supply.
Types of Transmissions
Which of the following is a form of amplitude modulation?
B. Packet radio
C. Single sideband
D. Phase shift keying
Which of the following is an example of a digital communications method?
D. All of these choices are correct
What type of modulation is most commonly used for VHF packet radio transmissions?
D. Spread Spectrum
Which type of voice mode is most often used for long-distance (weak signal) contacts on the VHF and UHF bands?
Which type of modulation is most commonly used for VHF and UHF voice repeaters?
Which of the following types of emission has the narrowest bandwidth?
A. FM voice
B. SSB voice
D. Slow-scan TV
What does the term "APRS" mean?
A. Automatic Packet Reporting System
B. Associated Public Radio Station
C. Auto Planning Radio Set-up
D. Advanced Polar Radio System
Which of the following devices provides data to the transmitter when sending automatic position reports from a mobile amateur radio station?
A. The vehicle speedometer
B. A WWV receiver
C. A connection to a broadcast FM sub-carrier receiver
D. A Global Positioning System receiver
What type of transmission is indicated by the term NTSC?
A. A Normal Transmission mode in Static Circuit
B. A special mode for earth satellite uplink
C. An analog fast scan color TV signal
D. A frame compression scheme for TV signals
Which of the following is an application of APRS (Automatic Packet Reporting System)?
A. Providing real time tactical digital communications in conjunction with a map showing the locations of stations
B. Showing automatically the number of packets transmitted via PACTOR during a specific time interval
C. Providing voice over Internet connection between repeaters
D. Providing information on the number of stations signed into a repeater
What does the abbreviation PSK mean?
A. Pulse Shift Keying
B. Phase Shift Keying
C. Packet Short Keying
D. Phased Slide Keying
What is PSK31?
A. A high-rate data transmission mode
B. A method of reducing noise interference to FM signals
C. A method of compressing digital television signals
D. A low-rate data transmission mode
Which of the following may be included in packet transmissions?
A. A check sum which permits error detection
B. A header which contains the call sign of the station to which the information is being sent
C. Automatic repeat request in case of error
D. All of these choices are correct
What code is used when sending CW in the amateur bands?
C. International Morse
Which of the following can be used to transmit CW in the amateur bands?
A. Straight Key
B. Electronic Keyer
C. Computer Keyboard
D. All of these choices are correct
What is an ARQ transmission system?
A. A special transmission format limited to video signals
B. A system used to encrypt command signals to an amateur radio satellite
C. A digital scheme whereby the receiving station detects errors and sends a request to the sending station to retransmit the information
D. A method of compressing the data in a message so more information can be sent in a shorter time
What is the approximate maximum bandwidth required to transmit a CW signal?
A. 2.4 kHz
B. 150 Hz
C. 1000 Hz
D. 15 kHz
What determines the amount of deviation of an FM (as opposed to PM) signal?
A. Both the frequency and amplitude of the modulating signal
B. The frequency of the modulating signal
C. The amplitude of the modulating signal
D. The relative phase of the modulating signal and the carrier
What happens when the deviation of an FM transmitter is increased?
A. Its signal occupies more bandwidth
B. Its output power increases
C. Its output power and bandwidth increases
D. Asymmetric modulation occurs
T2B07 (A) [
What could cause your FM signal to interfere with stations on nearby frequencies?
A. Microphone gain too high, causing over-deviation
B. SWR too high
C. Incorrect CTCSS Tone
D. All of these choices are correct
What is the approximate bandwidth of a VHF repeater FM phone signal?
A. Less than 500 Hz
B. About 150 kHz
C. Between 10 and 15 kHz
D. Between 50 and 125 kHz
What is the primary advantage of single sideband over FM for voice transmissions?
A. SSB signals are easier to tune
B. SSB signals are less susceptible to interference
C. SSB signals have narrower bandwidth
D. All of these choices are correct
What is the approximate bandwidth of a single sideband voice signal?
A. 1 kHz
B. 3 kHz
C. 6 kHz
D. 15 kHz
What is the typical bandwidth of analog fast-scan TV transmissions on the 70 cm band?
A. More than 10 MHz
B. About 6 MHz
C. About 3 MHz
D. About 1 MHz
Transmitting and receiving techniques
Which term describes the ability of a receiver to detect the presence of a signal?
D. Total Harmonic Distortion
What is a transceiver?
A. A type of antenna switch
B. A unit combining the functions of a transmitter and a receiver
C. A component in a repeater which filters out unwanted interference
D. A type of antenna matching network
Which of the following is used to convert a radio signal from one frequency to another?
A. Phase splitter
Which term describes the ability of a receiver to discriminate between multiple signals?
A. Discrimination ratio
D. Harmonic Distortion
What is the name of a circuit that generates a signal of a desired frequency?
A. Reactance modulator
B. Product detector
C. Low-pass filter
What device takes the output of a low-powered 28 MHz SSB exciter and produces a 222 MHz output signal?
A. High-pass filter
B. Low-pass filter
D. Phase converter
What is meant by term PTT?
A. Pre-transmission tuning to reduce transmitter harmonic emission
B. Precise tone transmissions used to limit repeater access to only certain signals
C. A primary transformer tuner use to match antennas
D. The push to talk function which switches between receive and transmit
Which of the following describes combining speech with an RF carrier signal?-
A. Impedance matching
D. Low-pass filtering
Interference & mitigation techniques
Which of the following is a way to reduce or eliminate interference by an amateur transmitter to a nearby telephone?
A. Put a filter on the amateur transmitter
B. Reduce the microphone gain
C. Reduce the SWR on the transmitter transmission line
D. Put a RF filter on the telephone
Which of the following may be a cause of radio frequency interference?
A. Fundamental overload
C. Spurious emissions
D. All of these choices are correct
How can overload of a non-amateur radio or TV receiver by an amateur signal be reduced or eliminated?
A. Block the amateur signal with a filter at the antenna input of the affected receiver
B. Block the interfering signal with a filter on the amateur transmitter
C. Switch the transmitter from FM to SSB
D. Switch the transmitter to a narrow-band mode
Which of the following actions should you take if a neighbor tells you that your station�s transmissions are interfering with their radio or TV reception?
A. Make sure that your station is functioning properly and that it does not cause interference to your own radio or television when it is tuned to the same channel
B. Immediately turn off your transmitter and contact the nearest FCC office for assistance
C. Tell them that your license gives you the right to transmit and nothing can be done to reduce the interference
D. Install a harmonic doubler on the output of your transmitter and tune it until the interference is eliminated
Which of the following may be useful in correcting a radio frequency interference problem?
A. Snap-on ferrite chokes
B. Low-pass and high-pass filters
C. Band-reject and band-pass filters
D. All of these choices are correct
What should you do if something in a neighbor�s home is causing harmful interference to your amateur station?
A. Work with your neighbor to identify the offending device
B. Politely inform your neighbor about the rules that prohibit the use of devices which cause interference
C. Check your station and make sure it meets the standards of good amateur practice
D. All of these choices are correct
What is a symptom of RF feedback in a transmitter or transceiver?
A. Excessive SWR at the antenna connection
B. The transmitter will not stay on the desired frequency
C. Reports of garbled, distorted, or unintelligible transmissions
D. Frequent blowing of power supply fuses
What might be the first step to resolve cable TV interference from your ham radio transmission?
A. Add a low pass filter to the TV antenna input
B. Add a high pass filter to the TV antenna input
C. Add a preamplifier to the TV antenna input
D. Be sure all TV coaxial connectors are installed properly
Which of the following methods is used to locate sources of noise interference or jamming?
B. Doppler radar
C. Radio direction finding
D. Phase locking
Higher Frequency = higher loss
Easy to use
not acceptable to interference from close metal objects
More expensive, especially for higher power handling
RG-8, RG-8X, RG-214
LMR 400, LMR 600
9913 or Hardline
Twinlead or ladder line
lower loss, if it is strung right
has to be looped if excess, can’t be near metal
Why is Low SWR important?
Protect the transmitter
Avoid stray RF energy around the ham shack — sometimes it can get into microphone and speaker wires and cause interference, even with good SWR. To avoid it getting into a Microphone, install one or more Ferrite chokes as a low pass filter on the mic cable.
Get the most of your signal out the antenna as possible
Common impedance is 50 ohms; “Characteristic Impedance”
How to measure
If you’re getting erratic readings, maybe a bad connector or water in the feed line
Sealed to prevent water from entering the feed line
PL-259 / SO-239 or UHF
commonly used at HF frequencies
Used by almost all ham radios
Different radios use different connectors for Power and Microphone. Most radios use the same connectors for external speakers and antennas
Preferred for microwave operation
Polarization matters around 20 DB Electric field = polarization. Magnetic field = perpendicular to polarization
Frequency and Wavelength
468 / freq in Mhz = total length in feet for a half wave dipole
Strongest Broadside to the antenna, weakest off the ends
Loading Coils to electrically lengthen an antenna
Traps on a dipole
Loading coil at the base of a vertical
Gain in reference to an isotropic antenna
You can either point an antenna directly at what you’re trying to reach or at an angle to bounce the signal off a mountain to reach your intended communication location
Beam or Yagi
Horizontal Polarization creates a tighter beam width so is used for SSB and long range whereas if you’re communicating with mobile stations such as on FM, Vertical polarization works better because that’s what they’re using
Angle of radiation is lower for ⅝ than a 1/4
Horizontal Radiation Pattern against grondplane
Magnetic field is parallel to the earth and the Electric field is perpendicular
Which of the following devices is most useful for VHF weak-signal communication?
A. A quarter-wave vertical antenna
B. A multi-mode VHF transceiver
C. An omni-directional antenna
D. A mobile VHF FM transceiver
What is the primary purpose of a dummy load?
A. To prevent the radiation of signals when making tests
B. To prevent over-modulation of your transmitter
C. To improve the radiation from your antenna
D. To improve the signal to noise ratio of your receiver
Which of the following instruments can be used to determine if an antenna is resonant at the desired operating frequency?
A. A VTVM
B. An antenna analyzer
C. A Q meter
D. A frequency counter
What, in general terms, is standing wave ratio (SWR)?
A. A measure of how well a load is matched to a transmission line
B. The ratio of high to low impedance in a feed line
C. The transmitter efficiency ratio
D. An indication of the quality of your station�s ground connection
What reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line?
A. 2 to 1
B. 1 to 3
C. 1 to 1
D. 10 to 1
What is the approximate SWR value above which the protection circuits in most solid-state transmitters begin to reduce transmitter power?
A. 2 to 1
B. 1 to 2
C. 6 to 1
D. 10 to 1
What does an SWR reading of 4:1 indicate?
A. Loss of -4dB
B. Good impedance match
C. Gain of +4dB
D. Impedance mismatch
What happens to power lost in a feed line?
A. It increases the SWR
B. It comes back into your transmitter and could cause damage
C. It is converted into heat
D. It can cause distortion of your signal
What instrument other than an SWR meter could you use to determine if a feed line and antenna are properly matched?
C. Iambic pentameter
D. Directional wattmeter
Which of the following is the most common cause for failure of coaxial cables?
A. Moisture contamination
B. Gamma rays
C. The velocity factor exceeds 1.0
Why should the outer jacket of coaxial cable be resistant to ultraviolet light?
A. Ultraviolet resistant jackets prevent harmonic radiation
B. Ultraviolet light can increase losses in the cable�s jacket
C. Ultraviolet and RF signals can mix together, causing interference
D. Ultraviolet light can damage the jacket and allow water to enter the cable
What is a disadvantage of air core coaxial cable when compared to foam or solid dielectric types?
A. It has more loss per foot
B. It cannot be used for VHF or UHF antennas
C. It requires special techniques to prevent water absorption
D. It cannot be used at below freezing temperatures
Which of the following is a common use of coaxial cable?
A. Carrying dc power from a vehicle battery to a mobile radio
B. Carrying RF signals between a radio and antenna
C. Securing masts, tubing, and other cylindrical objects on towers
D. Connecting data signals from a TNC to a computer
What does a dummy load consist of?
A. A high-gain amplifier and a TR switch
B. A non-inductive resistor and a heat sink
C. A low voltage power supply and a DC relay
D. A 50 ohm reactance used to terminate a transmission line
Radio Wave Characteristics
Radio Waves are electromagnetic waves that travel through space. They contain an electric field and a magnetic field. This is Non-ionizing radiation as opposed to ionizing radiation, that you’d get from plutonium. RF radiation does not have sufficient energy to cause genetic damage
They bounce off the ionosphere
Radio waves travel at the speed of light
300 million meters per second = 5280 ft/sec
Wavelength x Frequency = speed of Radio Waves
So, 300 divided by frequency in MHz = # of meters wavelength
We use # of meters to identify radio bands
HF 3 - 30 MHz
VHF 30 - 300 MHz
UHF 300 - 3,000 MHz or .3 - 3 GHz
Reflections cause multipath distortion. Sometimes you get the signal bounced off one mountain and onother at the same time and since they’re different dx apart, they’ll heterodyne out of phase and distort — move a few quarter wavelengths left or right. When you’re driving through a rough patch, the fluttering is called, “Picket Fencing”
If you have a digital signal, distortion causes errors
Shorter wavelengths penetrate buildings better than longer ones
The FCC specifies a Maximum Permissible Exposure limit for radio waves being close to where people live. It depends on how big the antenna, how much power output from the transmitter and at what frequency you’re transmitting. Below 50 MHz they mostly don’t care so much
On the other hand, on 2m you need RF exposure evaluation if you’re sending more than 50 watts Peak Envelope Power to the antenna
Frequency and power level of the RF field, Distance from the antenna to a person and Radiation pattern of the antenna all contribute to the RF exposure evaluation.
The human body absorbs more RF energy at some frequencies than at others, particularly higher frequencies
You can determine that your station complies with FCC RF exposure regulations either By calculation based on FCC OET Bulletin 65 or By calculation based on computer or By measurement of field strength using calibrated equipment
If the distance between your antenna and a person became very small while you were transmitting, say, if they touched it, they might get a painful RF burn
If you think you might have a problem with RF exposure limits, the easiest first step is to Relocate antennas
If you make a change to your station, re-evaluate
Since the FCC guidelines for RF exposure limits are primarily concerned with average exposure of people to radiation you must try to factor in duty cycle or what % of the time you’re transmitting
The Ionosphere reflects waves below around 30 MHz most of the time
Radio waves travel along the ground, also, just about 15% further than how far you can see around the curvature of the earth. In fact, we use the term, “Radio Horizon” to refer to The distance over which two stations can communicate by direct path. Dust is irrelevant. Moisture helps a tiny bit.
It has up to 4 layers called, D, E F1 and F2
The E layer occasionally refracts VHF signals. Whenever you experience strong, over the horizon signals on 10, 6 and 2, chances are, it’s Sporadic E propagation.
auroral reflection happens sometimes. Signals vary rapidly and are usually distorted
Occasionally ground waves will refract around a mountain or other large obstruction. When this occurs, we call it Knife-edge diffraction.
Sometimes you can get over the horizon using VHF or even UHF around 300 miles. This is Tropospheric scatter or troposcatter up to 300 miles or so
When small rocks hit the earth and burn up, as they’re burning, they reflect radio waves. This happens most often on 6 meters. This is called, “Meteor Scatter”. Usually, one must use special digital modes to take advantage of the very short bursts of available path
Temperature inversions in the atmosphere cause Troposheric ducting. Radio waves get trapped between layers of the ionosphere. Discovered during WWII, they thought those super incredible frequencies up there at 144 MHz would just punch right through and would never be intercepted. They were wrong, it turns out. Relatively common in the summer, allows reception of signals up to 800 or 1000 or even 3000 miles away. Above 90 MHz happens more often. Works well over oceans.
During auroral reflection, VHF signals exhibit rapid fluctuations of strength and often sound distorted
The ionosphere fluctuates influence based on the 11 year sunspot cycle. When there’s a lot of sunspots, the ionosphere works better for hams and you can hear more signals. This is especially true on higher HF frequencies such as 6 and 10 meters at night, shortly before dawn is best.