On August 3, 2018 the 442.000 repeater with an encode/decode tone set at 186.2 went live just in time for Summerfest, the annual Austin ham radio gathering. It is open for all licensed ham radio operators to use.
The repeater is in Austin’s “Museum District” on top of the Mid Century modern Cambridge Tower Condo at MLK and Lavaca Street near the AT&T Executive Education Center and the Bob Bullock Texas History Museum.
And if you’re on Allstar you can connect to it via these nodes:
27170 441.875 N5JGX North Austin 446.875 RX 100.0 PL
47371 145.570 AB5N Hot Springs, Arkansas
48668 145.550 KA6ATN Cedar Creek Lodge
48076 145.650 KA6ATN Austin Condo
48493 442.000 KA6ATN Austin Cambridge Tower 186.2 PL
Have fun with 442.000, that’s what ham radio is all about, having fun and helping people. The repeater is open for any events like bike races, marathons, Longhorn tailgate parties, etc if you want to use it for co-ordination.
The repeater will be a Bridgecom 40U into a Comet 9DB gain vertical. ERP is just over 100W. Coax will be under 20 feet for very low loss. The goal is to make an excellent coverage FM repeater with expansion capabilities into C4FM, DMR and Dstar. A large back-up battery system will be installed for emergency operations. Initially an AllStar Link will be active to connect to other repeaters and Nodes around the world. A basic AllStar Node configuration will be active which includes Hot Springs, AR. , Beckley W.Va., and Crosley, TX. Coverage into larger parts of the central Texas area will occur with the N5JGX repeater northward and additional Nodes near Bastrop and South of Austin. The system is open to all Amateurs. ETA is late July or August….sooner if nothing is delayed. Bob-AB5N
The Cambridge Tower repeater on 442.000 is dedicated to serving and supporting the community through volunteering and communications. Our services partly include:
Providing communications for local bike and other events benefiting local non- profits such as the Capital 10K
Demonstrating amateur radio at public events.
Preparing ourselves and the community for disasters large and small such as hurricanes, nuclear attacks, power outages (we have a battery backed up system) and other natural and manmade disasters.
Amateur radio, or “ham radio” as it’s often abbreviated, has been around since the earliest days of experimentation with radio communications. It was only as the number of amateur stations increased and interference started to be a problem that radio started to be regulated. In the U.S., this began under the Radio Act of 1912. Amateur radio stopped entirely during World War I, but was re-established after the war. It was codified internationally in 1927 and 1928, with standard amateur radio bands and call sign prefixes being established.
In the U.S., amateur radio is regulated by Part 97 of the FCC’s regulations. The beginning of these regulations outlines the purpose of the Amateur Radio Service:
(a) Recognition and enhancement of the value of the amateur service to the public as a voluntary noncommercial communication service, particularly with respect to providing emergency communications.
(b) Continuation and extension of the amateur’s proven ability to contribute to the advancement of the radio art.
(c) Encouragement and improvement of the amateur service through rules which provide for advancing skills in both the communication and technical phases of the art.
(d) Expansion of the existing reservoir within the amateur radio service of trained operators, technicians, and electronics experts.
(e) Continuation and extension of the amateur’s unique ability to enhance international goodwill.
You frequently hear about amateur radio operators helping maintain emergency communications during major disasters, such as hurricanes, earthquakes, and even in the wake of the 9/11 attacks on the World Trade Center. Often, this is done by having amateur stations relay messages into and out of the affected area, passing them from station to station to get them where they need to go (much as Internet routers pass packets of data along to their destination). Scientist and inventor Hiram Percy Maxim recognized the value of this technique in 1914, and to help coordinate these activities, he founded the American Radio Relay League (ARRL), the primary interest group for ham radio in the United States. Today, interest groups such as the Amateur Radio Emergency Service (ARES) maintain this capability, and the annual ARRL “Field Day” promotes being able to operate independent of mains power, as would be the case in emergency situations.
Amateur radio experimenters have helped develop new communications modes that were later widely used in commercial contexts. Hams, for instance, pioneered single-sideband (SSB) voice communications in 1933, a technique now in wide use elsewhere. Hams also pioneered many modes of digital communication that are reflected in modern communications systems such as cellular phones and Wi-Fi. This process of innovation is still going on today.
There are about 600,000 amateur radio operators in the U.S. today, and 2,000,000 worldwide. Anyone can join, though; in the U.S., visit Get on the Air on the ARRL Web site to find out how.
During emergencies, amateur radio operators may transmit messages to other amateur stations, subject to the privileges authorized for the class of license the amateur station control operator holds. For these transmissions, no special FCC permissions are required. Some amateur radio operators coordinate their communications through groups referred to as “networks” or “nets.”
Messages may be transmitted on behalf of unlicensed individuals, at the discretion of the amateur station licensee. These messages are referred to as third party communications. The FCCs rules permit an amateur station to transmit messages for a third party to any other amateur station within the jurisdiction of the United States. Amateur stations in the United States may transmit third party communications to amateur stations outside the United States under certain circumstances.
Amateur Radio Service Support to Public Safety Communications
In times of emergency when normal public safety communications are not available, there are alternative systems that may be used for this purpose. Current FCC rules state that amateur stations and operators are allowed to assist and support public safety communications in times of emergency. This article addresses the voluntary services provided by amateur operators, amateur service organizations and the relationships between amateur service organizations and public safety jurisdictions. Information about amateur services is also briefly described in the Public Safety and Homeland Security Bureau’s Amateur Radio Services web page.2
Amateur radio (also known as ‘ham radio’) services are regulated under Part 97 of the FCC rules.3 Amateur radio operators are licensed users who operate radio communications as a hobby or a voluntary service running within amateur radio frequencies allocated by the FCC4. To acquire an amateur radio license, individuals are required to pass a licensing exam that proves the individual possesses the operational and technical qualifications required to properly perform the duties of an amateur service licensee [47 CFR 97.503]. Currently, individuals may qualify for three classes of operator license: Technician, General and Amateur Extra.
When normal communications systems are not available, amateur stations may make transmissions necessary to provide essential communication needs in connection with the immediate safety of human life and immediate protection of property [47 CFR 97.403]. This provision of emergency communications is regulated by Part 97, Subpart E of the FCC’s rules. One advantage for amateur radio operators in public emergency communications is the wide range of available frequencies [47CFR 97.407].5
One service within the amateur radio services that uses amateur stations during periods of emergencies is known as the Radio Amateur Civil Emergency Service, or RACES.6 To transmit in RACES, an amateur station must be certified and registered by a civil defense organization or an FCC-licensed RACES station. RACES is administered by the Federal Emergency Management Agency (FEMA) and acts as a communications group of the government. Registered members of RACES are authorized to respond when a civil defense organization requests amateur radio assistance. Typically these activities occur during periods of local, regional or national civil emergencies such as hurricanes, earthquakes, floods or wildfires. RACES stations may only communicate with specified stations [47CFR 97.407(c), (d)].
It is important to recognize that the amateur radio stations participating in RACES are certified by their local civil defense organizations for this specific purpose. The operators are a valuable resource that provides emergency communication capabilities to their community. Civil defense organizations establish their own training and certification standards. Some localities â€” for example, Arlington County, Virginia7 – have more stringent training and certification standards than others. The key component of the RACES program is the direct and recognized affiliation between the amateur radio operators and local authorities since RACES may provide a critical alternative communications link for local officials. For example, RACES operators serve the county by passing critical emergency information from county officials with the County Emergency Response Team (CERT) to RACES operators at other locations.
Although RACES stations operate in conjunction with a federal, state, tribal or local jurisdiction, there are other options for amateur radio operators in emergency communications to include the Amateur Radio Emergency Service (ARES). Together with the National Traffic System (NTS), these services are broad programs of the American Radio Relay League (ARRL) which is a national association of radio amateur operators. ARES members are licensed amateur radio operators who volunteer to provide emergency communications services to public safety and public service organizations. Most individual ARES units are organized within a city, county or state and usually operate autonomously. The ARRL describes the ARES programs as follows: 8
“The Amateur Radio Emergency Service (ARES) consists of licensed amateurs who have voluntarily registered their qualifications and equipment for communications duty in the public service when disaster strikes. Every licensed amateur, regardless of membership in ARRL or any other local or national organization, is eligible for membership in ARES. The only qualification, other than possession of an Amateur Radio license, is a sincere desire to serve. Because ARES is an amateur service, only amateurs are eligible for membership. The possession of emergency-powered equipment is desirable, but is not a requirement for membership.”
Frequently, individuals interested in providing emergency communications are registered in both ARES and RACES. Dual registration allows continuity of operations if normal amateur operations might otherwise be prohibited.
RACES and ARES are collaborative services although they exist as separate volunteer entities. The ARRL encourages dual enrollment and cooperative efforts between both groups whenever possible. Both organizations remain a vital resource for the public safety community in times of crisis.
The purpose of this 442.000 repeater shall be:
1. To promote interest in Amateur Radio, electronics technology, and communications practice.
2. To assist fellow Amateurs in development of the radio art, and to provide educational opportunities to both Amateurs and non-Amateurs interested in radio communications.
3.To bring before its members such topics and equipment as would improve their knowledge of the state of the art.
4. To provide public communications services, to lend our full support and cooperation to restoring channels of communications in time of disaster, and to offer training in emergency preparedness skills.
5.To provide better communication through all phases of Amateur operation including, but not limited to, radio repeaters.
6. To support, among all Amateurs, lawful and responsible conduct, as embodied in the ARRL Code of Ethics.
7. No substantial part of the activities of this repeater installation shall attempt to influence legislation, and no activities shall involve intervention or participation in any political campaign on behalf of any candidate for public office.
A New Ham’s Guide
How to Use Amateur (Ham Radio) Repeaters by N4UJW
Simple enough for even me to understand!
This article will help the New Ham to be more at home on repeaters and understand the operation and procedures on Ham Radio Repeaters.
It contains a basic description of a ham radio repeater, how to use it properly and is written with the NEW HAM in mind for one of the most popular ham bands….2 meters.
What is a Repeater and Why is it Needed, and How Does It Work? What:It’s a two-way radio system that receives on one frequency, then re-transmits what it receives on another frequency; at exactly the same time. It’s nothing more than a “dumb electronic machine” with some smart people behind it.
Why it’s needed:Your mobile or hand held transceiver, has a limited range due to it’s antenna height with respect to the radio horizon and rf attenuating surroundings. Repeater systems are used to “transfer” your transmitted and received signals to much higher levels electronically using large, very efficient high gain antennas, low loss feedlines and a transmitter and receiver that is rated for heavy or continuous duty. A repeater “gets out” your signal and receives the station you are talking to with a far greater range and coverage area! You take advantage of the repeater’s higher elevation to increase your effective transmitting and receiving coverage versus your mobile or hand held transceiver!
How does a Repeater work? Here’s a simple block diagram of a repeater below:
More about Repeaters. See these very informative videos below from K7AGE, Randy.
A video is worth a thousand words! 3 Parts and a must see! (About 10 to 11 minutes each)
Part 1 –Getting started on 2M FM (Repeater Basics)
Part 2 –Getting started on 2M FM (Basic operation of a 2 meter HT)
The Basic Repeater Components: Antenna Most repeaters use only one antenna. The antenna is used on transmit and receive signals that are going into and out of the repeater. It usually is a high performance, high gain, heavy duty, and very efficient antenna located as high on a tower or structure as we can get it above the surrounding terrain.
Lots of repeater system antennas are located on a high hill or mountain.
Antenna systems for repeater use are usually very costly and have an omni-directional pattern. Feed line The feed line used on most repeaters is not just a piece of standard 50 ohm coax cable. A type of specialized feed line called “hard line” is usually used. It is very similar to cable tv line that you see strung between power poles around town. Look just above the telephone lines and you will see much larger “aluminum” cable. The signal loss with hard line versus regular coax is much lower than in standard coax, so more power gets to the antenna and weaker signals can be received due to the very low loss of the “hard line”.
Duplexer This device serves a major role in a repeater. The duplexer separates and isolates the incoming signal from the outgoing and vice versa. It prevents the receiver and transmitter from hearing one another by the isolation it provides. A duplexer has the shape of large tall cans and is designed to pass a very narrow range of frequencies and to reject others. It helps to reject very strong nearby frequencies from other repeaters or rf producers from getting into the repeater system.
Receiver Receives the incoming signal. This receiver is generally a very sensitive and selective one which helps weaker stations to be heard better by the repeater. It is set to receive the input frequency. It’s also where CTCSS (Continuous Tone Coded Squelch System) or “PL” decoding takes place.
Transmitter Most “machines”, as repeaters are sometimes called, have a transmitter composed of an exciter and a power amplifier. The exciter modulates the audio coming from the receiver which is tuned to the transmitting stations’s frequency at the proper transmit frequency, and the power amplifier simply boosts its level so the signal will travel further. Lots of repeaters use 100 watts or more. It simply takes the weaker received frequency from say a mobile or ht and re-transmits it (repeats) at a higher power level on a different frequency. On the 2 meter band, this separation between transmit and receive frequency is usually 600kHz either positive or negative in relation to the transmit frequency. On the 440 (70cm) band it is usually 5mHz positive or negative in relation to the transmit frequency.
The “transmit” frequency is the frequency you tune your radio to and is usually listed in various sources. For instance, if you see a repeater listing that says:
146.90mHz, minus or negative offset, Pl tone, 100….then you would program your radio to 146.90mHz , minus 600kHz with a PL tone of 100 into the memory for that specific repeater.
NOTE that most newer radios automatically set the offset (your actual transmit frequency) so you won’t have to.
Controller This is the brain of the repeater. It handles repeater station ID using either CW or voice, activates the transmitter at the appropriate times, and sometimes performs many other functions depending on the sophistication of the repeater. Some also have a DVR (Digital Voice Recorder) for announcements and messages. The controller is a small computer that’s programmed to control a repeater.
What is Offset? You may have seen the word “offset” mentioned in the Tramsmitter section above. So exactly what is a repeater offset you may ask? In order to listen and transmit at the same time, repeaters use two different frequencies. One for it’s transmit frequency and another for it’s receive frequency. On the 2 meter ham band these frequencies are 600 kHz (or 600 kilohertz) apart. On other bands, the offsets are different. As a general rule, if the output frequency (transmit) of the repeater is below 147 mHz, then the input frequency (listening) is 600 kilohertz lower. This is referred to as a negative offset. If the output is 147 Mhz or above, then the input is 600 kilohertz above. This is referred to as a positive offset.
Virtually all ham radios sold today set the offset once you have chosen the operating frequency automatically. Example: If the repeater output is 146.840 Mhz. The input, or the frequency the repeater receiver listens on is 146.240 Mhz ( 600 kilohertz below 146.840mHz).
If you have your radio tuned to 146.840 Mhz, (the repeater’s output frequency), when you push the mic button, your radio automatically transmits on 146.240 Mhz, 600kHz down from 146.840. When you release the mic button to listen, your radio switches back to 146.840 mHz to listen on the repeater’s output frequency. Note: There are exceptions to the rule so check your local repeater listings.
Standard Repeater Input/Output Offsets
6 meters 1 MHz
2 meters 600 kHz
1.25 meters 1.6 MHz
70 cm 5 MHz
33 cm 12 MHz
23 cm 20 MHz
(Note that input/output offsets are voluntary among local and regional “Frequency Coordination Groups”.
They are not fixed in stone by the FCC! They are “recommended” offsets for a particular area.
Your area may be different. Check with your local repeater operators.
Why do Repeaters use an Offset? Without having an offset between the transmit signal and the receive signal frequency, the repeater would simply hear itself when it was transmitting on the same frequency it was listening on!
Therefore, to use a repeater a user must use a different transmit frequency than receive frequency. Your actual transmit frequency is the exact same one that the repeater receiver is listening on. This is a form of duplex, or two frequency operation. It is known as half-duplex as you do not receive and transmit at the same time but normally use the push-to-talk button on your microphone to switch between the two. Cell phones use full duplex so each party can hear the other while the he/she is talking.
Even with the offset, the two frequencies are close enough that some isolation is required. Again, this isolation is done by the Duplexer. So you can see why some repeater components interact with each other and without the basic system components….nothing would work.
What’s all those tones about?
What is a PL or CTCSS Tone? PL, an acronym for Private Line, is Motorola’s proprietary name for a communications industry signaling scheme called the Continuous Tone Coded Squelch System, or CTCSS. It is used to prevent a repeater from responding to unwanted signals or interference. Tone Squelch is an electronic means of allowing a repeater to respond only to stations that encode or send the proper tone. In other words, if a repeater is set up to operate only when a PL tone of say, 136.5Hz is heard by it’s receiver, then it will allow the transmitting station access. If your station, (your mobile, base or hand held) does not transmit the tone that the repeater receiver has been programmed for, when you key up, then the receiver of the repeater does not hear you and will not be usable by your station until you set the proper tone in your radio to be transmitted when you key your mic. Any modern station may be set up to transmit this unique low frequency tone that allows the repeater to operate. If a repeater is “In PL mode” that means it requires a CTCSS tone (PL tone) to activate the repeater. Due to severe congestion of ham repeaters in some areas, most repeaters are “PL’ed”.
These repeaters were once called closed repeaters.
What Happens When You Key Your mic? Let’s “key up” a repeater and see what sequence of events are created within the repeater equipment when someone makes a transmission:
You set your transceiver controls for the 146.84 “machine” and listen to see if it is in use…nothing heard.
You key your mic and throw out your callsign….”This is KE5??? (insert your call sign) listening on the 146.84 machine”. Then you release the mic button.
Assuming your station is within range of the repeater….The repeater antenna which is usually very high on a tall building, tower, water tank, or even a mountain top, picked up your signal with its antenna on 146.24 (your transmit frequency set to the standard offset for this part of the 2 meter band of -600kHz, and the repeater’s receive frequency) and sent it down the feed line to the duplexer.
From there it was sent to the repeater receiver and converted to an audio signal (just like the sounds coming from your speaker)….sent to the controller (the brains of the repeater), then sent to the repeater transmitter and turned back into a much greater amplified radio signal on 146.84mhz (the output of the repeater)….sent to the duplexer….then thru the feedline to the antenna and out over the air. So your little pip squeak ht running only 1 watt may be increased to 20, 30, 50 or 100 watts or sometimes more using the repeater transmitter and its much higher gain antenna and high location!
A mobile, ht or base station that happened to be within range and monitoring the “.84′ machine heard your transmission on 146.84mhz (the repeater output frequency).
Since radio waves travel at about the speed of light….at the split second that you first keyed your mic, the above events took place and the repeater was receiving your signal on one frequency and re-transmitting your signal on a different frequency at the same time!
The mobile station that was listening on the output frequency of the repeater heard your callsign….keyed his mic and came back to you starting the process all over again!
A simple way of demonstrating what is going on with a repeater is to set a scanner or a second receiver tuned to the input frequency of a LOCAL active repeater…in the case above…146.24mhz and you can monitor its input (and the stations using it if they are local).
Then with your transceiver, monitor the output on 146.84mhz! You should be able to hear both the input signals and the output of the repeater as all this takes place on the air. You may notice some differene in the audio quality between the input and the output frequencies. This is normal.
How do you make a call on an Amateur Repeater? First, LISTEN AND LISTEN SOME MORE…… to make sure that the repeater is not already in use. When you are satisfied that the repeater is not in use,set your transmitter power to the minimum and increase only as needed to make contact with the repeater, begin with the callsign of the station you are trying to contact followed by your callsign. e.g. ” N4??? this is N3???”. (The N3??? is your callsign). If you don’t establish contact with the station you are looking for, wait a minute or two and repeat your call.
If you are just announcing your presence on the repeater it is helpful to others that may be listening if you identify the repeater you are using AND your callsign. e.g. ” This is N3??? listening on the 84 machine or you could also say This is N3??? listening on 146.84 Dallas or the location of the repeater if known. This allows people that are listening on radios that scan several repeaters to identify which repeater you are using. If the repeater you are using is a busy repeater you may consider moving to a simplex frequency (transmit and receive on the same frequency….. see more below), once you have made contact with the station you were calling. Repeaters are designed to enhance communications between stations that normally wouldn’t be able to communicate because of terrain or power limitations.
If you can maintain your conversation without using the repeater, going “simplex” (both stations on same frequency in a different part of the band) will leave the repeater free for other stations to use that can’t establish simplex communications!
Repeater EtiquetteandReporting Emergencies The first and most important rule before using a repeater is to LISTEN FIRST. Nothing is more annoying than someone that “keys up” or DOUBLES in the middle of another conversation without first checking to make sure the repeater is free. If the repeater is in use, wait for a pause in the conversation (watch your S meter and wait for it to drop indicating the repeater is listening) and simply say “Emergency, Emergency, Emergency”, and wait for one of the other stations to acknowledge your call. If for some reason you are not heard, then repeat the 3 “Emergencies” again…then if you are still not heard, try another nearby repeater.
This is not CB radio!
Don’t use CB lingo on any ham band such as 10-4, what’s your 20, etc…..don’t say BREAKER! Using the words BREAK, or BREAK, BREAK or BREAK, BREAK, BREAK or any combination of them on Ham radio can be misunderstood by an operator depending on his experience.
The word “break” or combinations of it carries many different meanings in the ham community and in the English language.
According to THE EMERGENCY COORDINATOR’S MANUAL Edited by Steven Ewald, WV1X andPublished by The American Radio Relay League, Inc., Quote from the “General Procedures section….http://www.arrl.org/files/file/Public%2520Service/ECMANUAL.PDF
“16) The word “break”isnever used UNLESS there is an emergency.”
Then further down in the manual, it appears to contradict or discourage the use of the word/s BREAK in the above statement:
“Note: The practice of using “BREAK” or “BREAK BREAK” to announce distress traffic should be strongly discouraged;it has no universally understood meaning.
So rather than have confusion…use plain language!
SO HOW DO YOU REPORT or ACT ON AN EMERGENCY ON A HAM BAND? Many hams use the wording, “BREAK, BREAK, BREAK”, (the word “break” repeated 3 times in a row). This is accepted practice on the hf bands where noise may be a problem but on repeaters, usually noise is not a problem, so using “plain” language such as “EMERGENCY”, REPEATED 2 OR MORE TIMES can be used to announce that there is an emergency and the frequency is needed to relay vital information….if you hear an “Emergency” call during your conversation with another station….stop transmitting, listen….and then acknowledge the station calling the emergency and let them have the frequency immediately! Don’t delay them by saying something on the order of “Stand by breaker” and then carry on your conversation with your contact. Seconds wasted doing this may COST a life! Listen to them carefully and write down the details of their emergency. They will give you the details of the emergency. Then pause for a moment and wait before you go back to him…….many other hams who heard the emergency call may be responding ALL at the same time.
If someone “beats” you to getting back to him, let him take over. Do not break into the conversations UNLESS there is a need for a relay. Under certain situations due to distances involved with mobiles and repeaters, you may be able to hear a mobile BETTER than the repeater on the input frequency of the repeater. It is a good idea to monitor the input if possible if the station reporting the emergency is having trouble getting into the repeater. You may be closer to him than the repeater and can hear him better!
Whether or not the station reporting the emergency is a base station OR mobile, try to monitor the input of the repeater if there is difficulty in the emergency transmission.
IF YOU ARE REPORTING AN EMERGENCY: When using VOICE, use the international standard “MAYDAY” or universally understood “EMERGENCY” to announce traffic of life-or-deathimportance.
The procedure should be:
1.Select the repeater frequency.
2. Wait for a space between transmissions if the repeater is busy.
3. Key your mic and state…”Emergency, Emergency, Emergency” unkey.
4. Wait for a response from the repeater users. If you get no response, try another repeater.
When you do make contact, state your call sign and give as many details as to the emergency as possible. Don’t panic, speak slowly and clearly so the details will be understood the first time! Always give details as exact and specific. Give the details of the exact LOCATION of the emergency using enough description of the location so it can be found easily by first responders. Don’t say….on highway 60 and leave it at that. The emergency vehicles need exact locations if at all possible. Remember, seconds or minutes saved equal lives in many cases!
Give number of “victims” if possible. Is there is fire involved, downed power lines, immediate road blockage due to wreckage creating further dangers? DETAILS, DETAILS, DETAILS.
The person on the other end of your transmission is most likely copying the info to paper so he can relay it to the appropriate authorities. Help him help you!
If by some chance you have to use Morse code when reporting an emergency, then: The standard CW signal is “SOS,” sent as a single character–not spaced as three letters.”
EXAMPLE: DIT DIT DIT DAH DAH DAH DIT DIT DIT and NOT, dit dit dit SPACE dah dah dah SPACE dit dit dit. NOTE: Many repeater systems allow touch tone key pad entry of “911” DIRECT TO the 911 operators and the emergency reporting system. Check with your repeater system owners or trustees for info BEFORE YOU NEED TO KNOW.
When making a 911 call direct from your station, make sure the 911 operator understands that you are calling via ham radio and she/he can not talk or (be heard by you) until you have unkeyed your radio. Use of the term “over” is very helpful between you and the 911 operator. It is not like using cell phones. It is a one way (half duplex) transmission using a repeater and not simplex as with regular cell phones or land lines. Both parties CAN NOT talk at the same time!
Use plain languageon a repeater. If you want to know someone’s location, say “Where are you…. or what’s your location?” If you want to know whether someone you’re talking with is using a mobile rig or a hand-held radio, just ask: “What kind of radio are you using?” You get the idea. Most repeater use is of a “local” nature so signals will be usually of very high quality. The use of the phonetic alphabet is very helpful at times.
Don’t call CQ to initiate a conversation on a repeater. Just simply listen to make certain the repeater is not in use and then key your mic and say your call sign and “listening”.
If someone happens to be listening and they want to talk to you they will respond.
When you are using the repeater leave a couple of seconds between exchanges to allow other stations to join in or make a quick call. Most repeaters have a “Courtesy Tone” (a short…beep or series of beeps) that will help in determining how long to pause. The courtesy tone serves two purposes. Repeaters have a time out function that will shut down the transmitter if the repeater is held on for a preset length of time (normally three or four minutes). This ensures that if someone’s transmitter is stuck on for any reason, it won’t hold the repeater’s transmitter on indefinitely. (Don’t laugh, many microphones get lodged in the fold of car seats and keep a repeater busy until it times out. Of course if it is not noticed soon by the mobile operator…..the control operator of the repeater may have to shut down the repeater until the problem is corrected.) When a ham is talking and releases the push-to-talk switch on their radio, the controller in the repeater detects the loss of carrier and resets the time-out timer. When the timer is reset, the repeater sends out the courtesy tone. If you wait until you hear this beep (normally a couple of seconds), before you respond, you can be sure that you are pausing a suitable length of time. After you hear the beep, the repeater’s transmitter will stay on for a few more seconds before turning off. This is referred to as the “tail”. The length of the tail will vary from repeater to repeater but the average is about 2 or 3 seconds.
You don’t HAVE to wait for the “tail to drop” before keying up again, but make sure that you hear the courtesy tone (if used) before going ahead. Note: If you don’t wait for the beep, the time-out timer may not reset. If you time-out the repeater, YOUR conversation AFTER the time-out will not be heard. The repeater time-out function does not care if you are still talking or not; and the station on the other end may rib you about hogging the machine and you will have wasted all those words! What is Doubling? When two stations try to talk at the same time on the same repeater, the signals mix in the repeater’s receiver and results in a buzzing sound, squeal, distorted sound or severely jumbled and broken words.
When you are involved in a roundtable discussion with several other stations it is always best to pass off the repeater to a specific person (station) rather than leave it up it the air. e.g. “W3??? to take it, this is N3???”, then unkey; or…….
“Do you have any comments Fred?, this is N3???”; un key.
You could also say “OK…that’s all I have…..back to you Fred” or the next person in rotation… (un key)….
Failing to use this or other techniques is an invitation to total confusion.
As a point of interest, a repeater will usually lock into the strongest of two FM signals. This is the nature of FM. The strongest signal usually wins.
Signal Reports on a Repeater Lots of new hams don’t understand that the S meter on their radio is only reporting the relative strength of the repeater system and NOT the signal strength of the station they are talking to unless they are in the simplex mode. When the repeater is transmitting, it may have an output greatly exceeding that of the station IT is listening to. Remember the station it hears on the input frequency of it’s receiver may be on a hand held radio and only a few blocks from the “machine” or it could be a mobile radio in a vehicle out on the fringes of the repeater coverage area or a base station running a high gain antenna and 100 watts from the next county or in some cases, the next state. To a third party, (another ham), listening to the machine on the repeater output, all of these stations would have the same S meter reading on his S meter! As long as the repeater can detect the signals and is working properly as it is setup, then all stations, (to the third ham), will “appear” to have the same signal strength on the S meter. Remember, the S meter is only reporting the relative strength of the repeater when it is transmitting and not the individual stations! So all that being said, how do you give an accurate signal report to the station you are talking to?
JUST USE PLAIN ENGLISH! Listen to the background sounds of his AUDIO coming from your speaker in between words and sentences. Don’t even look at your S meter.(Assuming the repeater has a good strong signal into your location).
If there is no noise other than room background, road, passenger or other sounds that could be picked up by his microphone, then he would be said to have a FULL QUIETING signal into the repeater…..receiver. NOT 50 OVER S9, S9, OR ANY COMBINATION on your S meter. The term “Quieting” refers to the carrier level of the transmitter being strong enough to “quiet” the background hiss on the frequency. If some background noise such as the hiss that is commonly heard in an FM receiver is heard on the transmitter signal, then it would not be considered “FULL QUIETING”. There are times when either station using a repeater may be getting into the repeater receiver with very little signal and the repeated signal will have lots of noise on it. Although the repeater signal may be full quieting when the weak station stops transmitting, the weak station can not be considered to be full quieting into the repeater so you would give the other station a report on his signal and not the repeater. Don’t get confused with this. If his audio is perfectly understandable with 100 % copy and there is NO “noise” in the background other than the above, then an accurate report for him would be, “You’re full quieting and 100 % copy into the repeater. Anything less than the above is usually given in various ways using an exact as possible description of his signal. “Audio” reports are a matter of interpretation by individual ears. We as hams are in the “business” of communications , not HI FI broadcast FM! We can only sound as good as the FCC will allow our transmitters to sound! If you are having extreme difficulty copying the other station, he may also be having the same problem with you, but remember he is hearing the repeater signal, not yours direct and so are you. Try to get him to go “simplex” if he is coming closer to you in a few minutes. See hint below. If the transmissions get so ruff that neither can copy the other, then just give your call sign and clear off the repeater for others to use while he gets closer or higher or changes his transmitting setup. Not all conversations are completed to the end under adverse conditions or operating situations….be patient.
HINT….If the station is in and out of range of the repeater you and he were using and is coming in your direction…try him on a simplex frequency! He may be loud and clear direct on simplex and only a few miles away and getting stronger all the time but he is getting farther from the repeater! Another situation that can happen during a new contact is that you and he did not exchange locations at the first of the contact. Both you and he are using a repeater 50 miles away. Then after several minutes you discover in your conversation with the other station that he is in the same town as you and only a couple of miles away! Time for simplex! Don’t hog the repeater.
Simplex operation generally means station to station or direct communication on the same frequency between two stations and not using a repeater. Use the least amount of output power needed to carry on the contact. Simplex should be used when the two stations are close enough to carry on a conversation without the use of a repeater and will help in congested metro areas with a limited number of repeaters. Simplex should always be used if possible rather than a repeater. See chart below for suggested simplex frequencies. (Highlighted in gray)
Repeater input and output frequencies highlighted in yellow.
2 Meter Band Plan as suggested by the ARRL (144-148 MHz):
General CW and weak signals
EME and weak-signal SSB
SSB National calling frequency
General SSB operation
New OSCAR subband
Linear translator inputs
FM repeater inputs
Weak signal and FM simplex (145.01,03,05,07,09 are widely used for packet)
Linear translator outputs
FM repeater outputs
Miscellaneous and experimental modes
National FM Simplex Calling Frequency
YOUR FIRST CONVERSATION AND CONTACT ON A REPEATER!
That most exciting day just arrived! You now have passed your Technician Class exam and have been issued your first call sign by the FCC.
You have your station all set up and you are ready for your first contact on a repeater! You chose a local repeater frequency and dial it up on your rig. You just keyed your mic, gave out your call sign and now you hear……..your call sign and someone coming back to you with his call sign…..he un keys and the repeater is waiting for YOU!
BRAIN LOCK SETS IN! “What do I do? What do I talk about? Will I remember all those rules, regulations, theory and all that other stuff I had to study?
The simple answer is…….probably not……but don’t worry!
First thing….try to write his call sign down and if he gives his name, that too. Lots of good operators recognize a new ham instantly on the air and they will guide you with patience, understanding, maybe some fun prodding and picking at you to get you to relax and have fun with your new license.
He will WELCOME you!
A good operator will never make you feel unwanted on the air. He may ask you to repeat your call sign just to make certain he understood who he is talking to and if you forget to give your name, he will ask for it. Most hams don’t like to talk to a “call sign”, so getting names and also locations helps to start the conversation.
If you make mistakes….he will most likely let you know what you did wrong and inform you as to the correct way in a friendly manor.
Don’t be surprised if he asks you all the questions instead of the other way around. He is just trying to get you to feel relaxed on the air. As your experience grows in ham radio, aways try to remember your first contact and how excited and nervous you were. Now it’s your turn and you are the one responding to a new ham and his first contact! Make him feel at home and…….be a good operator…..like your first contact was! Repeater ID…..you and it! You must transmit your call sign at the end of a contact and at least every 10 minutes during the course of any communication. You do not have to transmit the call sign of the station to whom you are transmitting. Never transmit without identifying. For example, keying your microphone to turn on the repeater without saying your station call sign is illegal. If you do not want to engage in conversation, but simply want to check if you are able to access a particular repeater, simply say “(your call sign…… testing).”
All ham radio stations, including repeaters AND YOUR STATION are required by the FCC to have a control operator monitoring the station while it is on the air. You are the control operator of your station.
Control operators are usually the owners, trustees or other designated licensed operators of a repeater system. They sometimes stay quietly in the background just listening to the every day operation of the “machine” for technical problems, proper use, FCC rule breaking, etc on a particular repeater.
They have complete control of whether a repeater is on the air or off and have the ability to stop it’s operation at any time! Use the repeater to the best of your ability and within the FCC rules.
Report any un-authorized use of a repeater to the repeater owner or person responsible for the operation of the repeater.
One last thought….SUPPORT YOUR LOCAL REPEATER/S. It takes LOTS of money to maintain a repeater and the money has to come from somewhere. If you can’t donate funds, then donate your time, assistance, equipment, knowledge, labor or anything of value to the repeater owner to help keep it on the air. It will be appreciated! Even simple things like mowing the grass around the repeater area is certainly appreciated. If the repeater is on a mountain top, enjoy the view while you are there. All repeaters need some kind of care from time so volunteer your time when others don’t.
WARNING TO NON-LICENSED STATIONS! Only licensed Amateur Radio Operators are authorized use of ANY Amateur Radio transceiver including repeaters in the transmit function.
SEVERE PENALTIES ARE ENFORCED BY THE FEDERAL COMMUNICATIONS COMMISSION!
LICENSED HAMS HAVE WAYS TO DETECT BOGUS CALL SIGNS!
DON’T TRY IT!
DON’T FORGET …..ID YOUR STATION THE REPEATER WILL NOT ID FOR YOU….IT ONLY ID’S ITSELF! After all……it’s only a dumb “machine”!
Five “MUST-HAVES” we considered when buying a two-way radio repeater for Cambridge Tower
Credit: By Ron Kochanowicz, BridgeCom Systems, Inc., BSEE, KCØQVT
There are many two-way radio repeaters on the market. It’s important to pick the right one for your application and budget. You definitely want to be happy with the result of your repeater buying decision. The following information is a brief guide of what I believe is five “MUST HAVES” to consider.
1. Receiver – The repeater you purchase MUST have a good receiver. This requirement should be at the top of the list. If your repeater cannot ‘hear’ very well, then it’s not very good and range will be limited.
There are three key parameters to look for when considering a receiver: Receiver sensitivity, Receiver selectivity, and Intermodulation rejection:
|A. Sensitivity – Is a measure of the minimum signal level required to produce a specified output signal of a specified signal to noise radio (SINAD). In repeater systems, this measurement is often given in microvolts or uV at 12 dB SINAD. The smaller the number in microvolt the more sensitive the receiver. For example: 0.25 uV at 12 dB SINAD is a very good receiver.
B. Selectivity – Is a measure of the how well the receiver ‘hears’ only the wanted signal and rejects all other signals nearby in frequency. Selectivity is measured as a ratio in dB comparing the signal strength received against that of a similar signal on another frequency. The higher the number, the more selective the receiver.
C. Intermodulation Rejection – Is a measure of how well the receiver handles the various unwanted harmonics created by the receiver itself. When a receiver is doing its job, it creates unwanted signals that can interfere with the received signal. Intermodulation Rejection indicates how well the receiver rejects these unwanted products. The higher the number in dB, the better. When this number is 70 dB or higher, it indicates quality parts are being used in the receiver construction.
One more important fact: The repeater’s antenna should be mounted as high in the air as possible to make the system work optimally.
2. Transmit Power – This specification, measured in Watts, is probably the one Repeater specification that all of the attention. Having as much RF Power as possible has merit, however, many things must be considered when buying a repeater. The goal is to consistently get as much transmit power out of the repeater without destroying it or reducing its life. It’s important to consider how often the repeater will be transmitting and for how long. For example, if a repeater spec states it produces 50 Watts, the question to ask is: How long can it deliver 50 Watts without interruption? If not very long, it might only be good at 25 Watts. Therefore it’s important to consider the manufacturers’ duty rating and cooling process and how it meets your application.
A. Systems Example: As transmit power is considered, power loss through the duplexer, power loss through the antenna feed line, and power gain at the antenna must also be considered. A simple example illustrates this point: If
you have a 50 Watt repeater, duplexer, 100 FT of LMR-400 feed line, and a 6 dB gain antenna. The loss through a duplexer is typically 1.5 dB. This brings the output down to 37.5 Watts to the feed line. The loss through the feed
line brings the power down to 26 Watts. The antenna adds 6 dB of gain and now your effective radiated power (ERP) is 104 Watts.
B. Adjustable Transmit Power: The repeater you consider must have the ability to adjust the transmit output power. Can it be dialed from 0 Watts to Max? Adjustable output power provides for a lot of flexibility if you consider using
the repeater as an exciter for an external RF Power Amplifier. External RF Power Amps are often specified as 10 Watts INPUT 100 Watts OUTPUT or 30 Watts IN, 100 Watts OUT. If you can dial your repeater back to 5 or 10 watts,
it extends the life of your repeater and lets the external RF power amp do much of the work.
C. Cooling: The next ‘must have’ for a repeater transmitter is sufficient cooling. You need to make sure your repeater transmitter is kept cool. This will increase the lifespan of the repeater as it will not have to work as hard in delivering power. Cooling is very important. Forced air is the best. At least one fan is required and two is even better. If the repeater is doing 5 Watts or more on a 50% duty cycle rating or higher, it is advisable to have forced air cooling your transmitter and power supply.
3. Power Supply with built-in battery charger: For ease of use and install, the repeater you purchase must have a built-in power supply. Having a built-in power supply will alleviate a lot of aggravation because you won’t have to obtain the correct power supply to run your repeater. The manufacturer has already done this for you! The repeater should also have the ability to be connected to an external DC source like a battery or external power supply. In addition, if there’s a built-in battery charger, then the internal power supply can trickle charge the battery.
4. Built-in Controller: Your repeater must have a controller and the repeater you purchase should have a basic built-in repeater controller. This will save you the task of connecting the repeater to an after-market controller. The ideal controller features that should be built in are:
1. Decode / encode CTCSS tones and DCS codes.
2. CW station ID.
3. Courtesy Tone.
4. TX Timer Timeout and TX Hang Timer.
5. DTMF remote management capability.
6. Narrow (12.5 kHz) and Wide band Capable.
7. Ease of programming.
5. Accessory Port/Expansion – This feature is a BIG ‘must have.’ The accessory port is where the magic can happen and can make a repeater very versatile and flexible. For example, do you want to connect an external controller that allows for voice updates? Do you want to connect a digital modem and turn your repeater into a digital repeater?
If so, are the proper connections available? Here are the 5 signal input / outputs the repeater accessory must have:
1. Receiver Discriminator Output – Unsquelched, unfiltered based band flat audio.
2. COS Output / COR Output – Received a carrier or decoded a CTCSS or DCS code.
3. PTT Input – External PTT Input line to cause repeater to transmit.
4. TX Audio Input – Audio to be transmitted by the repeater.
5. TX BASEBAND Audio Input – Unfiltered TX DATA or AUDIO.
While this list is not exhaustive, it does bring to mind five key MUST-HAVES when considering purchasing a new repeater. Warranty and customer service / support is also of strong consideration. You want make sure you have somebody to call in the event there’s a problem.
1. Good Receiver – less that 0.25 uV at 12 dB SINAD
2. Solid, consistent transmit Power with adequate cooling
3. Built-in Power Supply with built-in battery charger
4. Built-in Controller
5. Accessory Port/Expansion