Backcountry Radio Systems

Disclaimer: I use the term "we" to refer to the radio circle, an informal collection of friends that are also into backcountry radio. This use of the word we does not infer we are an organization, or a group at all. Just a bunch of radio enthusiasts coordinating our abilities to help keep the event safe and healthy for everyone. We do not represent anyone but ourselves.

We use a diverse collection of radios at a gathering. These range from CBs, to FRS, to GMRS, to HAM. CB, of course, is the old standby for many years. CB handhelds are available rather cheaply, used, and so they are somewhat plentiful. They also can communicate with people in vehicles that have mobile CB radios. The main problem with CBs is the limited range, and they are prone to becoming useless if skip is bad. Skip is when atmospheric conditions enable a radio signal to "skip" hundreds of miles. I can think of more than a few times were I could hear truckers 200 miles away, but couldn't talk to the people I wanted to a few miles down the trail.

FRS radios are also availably cheaper, but these aren't to be confused with a real radio. FRS radios only put out a 300-500 milliwatt signal, limiting their range to under a 1/2 mile in the woods. The other problem for us, is that they are also not repeater capable. The lack of this feature and the poor range is why we don't use them. GMRS radios are a cross between the UHF Ham radios, and an FRS. The main difference is that most GMRS radios put out 2 watts or more, and are repeater capable. (except the new Motorola DX). A repeater is a special transceiver that takes the weak signal from a handheld radio, and rebroadcasts it at more power. It can give you a 30 mile range, way more than you would have with just a handheld radio.

The Hams use whatever they normally carry when not at a gathering. The last few years I've carried a Yaesu FT-51R. I used to carry an Alinco 580T for 4 years previously. Others I know carry Kenwoods, or Icoms. Many ham radios marked as CAP/MARS compliant are easily modifiable to work on GMRS frequencies. I have a collection of modifications for many ham radios here. Another thing the hams do is swap out their dual band antenna, for a GMRS one. Using an antenna tuned for the GMRS band is easier on the radio, and you'll have better range and clarity.

When it comes to our preferred GMRS radios, a few years ago we standardized on Maxon 210+3s, which were 2 watt, and had a AA battery pack. These became discontinued though, as FRS became popular in the late 90s, leaving no GMRS radios on the market at all. Finally, Kenwood came out with the TK-3101 FreeTalk XL. This is a pretty nice radio, except for it can only be programmed at the factory, and some people have had problems with replacing the AA battery pack, which is a bit hidden behind the belt clip. We got our small collection of Kenwoods from JCRE (who seem to have gone out of business). These are durable units, and have the lightest weight, smallest size, and best audio. The main problem we found is the automatic squelch is too high, so it suffers on reception.

Recently, we have found a new GMRS radio, The Pryme PR-460 "Clear Connect" or "Pro Connect". This is a nice unit with twice the power (4 watts) of most GMRS handhelds. It also has a nicely sensitive receive, and feels like a ham radio, unlike the Maxon. We got our collection of PR-460s from Alabama Radio, who have been great to work. Pryme also makes a good series of external mikes and earphones. Another feature we like is that there is a 6 AA powered programmer unit available for programming these, which is more convienient than sending them to the factory. We prefer equipment that can be field maintained. btw - if you own one of these programmers, the manual is wrong about how to set FRS frequencies. Email me for info on the manual corrections for the programmer. One important trick is is how to get the AA battery pack on either unit. I've found the best way is to hold the radio upside down, and while holding the pack in place with one hand, I whack it with the palm of my hand, and it'll go right on. Otherwise, the AA pack is designed to drive you crazy with frustration.

Our current repeater is a homebrew rig from Hamtronics kits, salvaged parts, or stuff we already had. It's run for for several years, until recently it went up in smoke while being bench tested. It's now back in service after replacing about 15 parts, including the duplexer. We replaced the old and flaky CelWave 6 chamber duplexer with a new TX-RX one.

It originally started it's life as a simple repeater controller between two GMRS radios. Needless to say, we discovered the range wasn't so good. First the transmitter was switched to a Ramsey kit, and then a Motorola Flexar receiver. It was later upgraded to the Hamtronics transmitter and receiver, which has worked much better. The Motorola was using too much power, and the Ramsey wasn't very good. During all of this time, it's used a heavily modified NHRC-2 repeater controller. The entire system runs off a 50 Watt solar charged battery system. Up till now, we've used a 36 foot Radio Shack mast, (made by Rohm) and a 7DB CelWave UHF fiberglass antenna.

We've recently upgraded our repeater to a 10 watt, Motorola GR1225 portable, which we got a great deal and service from Frontier Radio in Denver. This unfortunately required a larger solar system of about 100 watts. This was done by adding a UniSolar unbreakable 64 watt panel and a UniSolar 32 watt flexible panel from Jade Mountain, and 2 - 235 Amp Hour Trojan T-125 deep cycle batteries, along with a 24 Amp Lyncom charge controller.

Just to top things off, we recently have switched to a New Wave antenna mast which we got from the Old Antenna Lab. This is a nice 7 section 40 foot telescoping tube, made of aircraft aluminum. It easier to put up than the Radio Shack mast. Because we had also noticed that with a 7db antenna, the signal often went over our head, we are now using a Decibel Products, DB633 fiberglass Omni at 3DB. The guy lines are 1/4 UV resistsnt Dacron from The Wireman, and consists of 3 - 23 1/2 short pieces, and 3 - 58 long pieces.

Radio Usage

Over the years we've developed a certain protocol on using radios. Part of this is based on practicalities, like the fact that most folks aren't as into knowing all the ins and outs of this technology as we are. They just want to be able to communicate with other individuals.

When transmitting, please make sure you wait for the previous person to be finished talking. When they are using the repeater, you also have to wait for the "squelch tail". This is the brief moment of static you'll hear when somebody is done transmitting. Depending on the repeater, there may also be a "Roger Beep", to signify the other person has stopped transmitting. When talking to the repeater, the ideal time to transmit is between the Roger Beep and the squelch tail. Take a break to allow somebody else to break in if need be, and the start transmitting... before the squelch tail kicks in. If you don't get this short window, or when talking Simplex, (not through the repeater.) let the squelch tail get done, or you will cut off the beginning of your first sentence, and you'll have to repeat yourself.

Also when first keying the radio it is advisable to hit the transmit button and take a breath before talking. This gives enough time for the squelch to break on the receiving radios so that the first word of your sentence is not cut off.

If you find yourself talking for more than a short while, please remember that other people may need to talk on the same frequency, so take a pause now and then to allow other people to break in. Many times the person that may need to break in, could be far away, and have a weak signal.

Please try to resist the urge to jump into all conversations on the radio. If you are not directly involved in the issue at hand or have something important to add to it, you may just be confusing the situation. Also understand that unnecessary chatter on the radios is annoying to many and can cause folks to turn off their radios to avoid the chatter, which causes them to be unreachable in emergencies.

When done a conversation, many people finish by saying "on the side at [location]", or some variation of that. This is to let other folks in the radio net know your last location. This is useful if somebody needs communication to that location, or needs to find that person face to face.

If you need to break into a busy conversation because you have relevant information, or a serious emergency more critical than what is already being discussed, try saying "break" during a pause. If you are actively in a conversation and hear a call for a break, you can help by saying "go break".

When possible, talk to somebody using "Simplex", which may result in a better signal if they are closer to you than the repeater. On the Maxons, this is controlled by the "Duplex" button. The word Simplex, or just an "R" (for repeater) appears in the display. On the PR-460s, channel 8 is the main frequency in Simplex mode, and channel 9 is the same frequency in duplex (repeater) mode. If you can reach somebody Simplex, please consider switching to a different channel. Just say "Going to channel 3". The first 7 channels on a Maxon or a PR-460 are the same as the first 7 FRS frequencies. This is useful because all FRS and GMRS radios share the first 7 frequencies.

FRS/GMRS Freqencies

First some back ground and theory. There are 15 GMRS channels. 7 are for simplex only (also known as the iterinerary channels), these 7 are the same as the 7 FRS channels. The other 8 can be for Simplex or repeater operation. One of these is a US emergency channel, 462.675. This gives us a total of 23 possible combinations for GMRS.

GMRS/FRS Simplex

All GMRS radios we've seen share there first 7 frequencies with FRS. This is one of the reasons we like GMRS, because it's getting more and more common to find these at gatherings. This lets us interoperate with people that have FRS radios, which is really useful during something like a search for a lost child and the parents of friends have FRS radios.

462.5625 462.5875 462.6125 462.6375 462.6625 462.6875 462.7125

GMRS only Simplex/Repeater

These frequencies can only be used by GMRS or Ham radios. Simplex is communicating on one of these without going through a repeater. When using duplex mode to talk to the repeater, the frequency is automatically shifted up +5, to talk to the repeater, which then rebroadcasts the signal at much higher power. For example, if transmitting on 462.550, this is shifted to 467.550, and the repeater relays this at 462.550.

The repeater is used to increase the range of the handhelds, by rebroadcasting a weak signal on the higher frequency, at with much more power. Also a repeater is usually setup on a hill. A big hill will prevent two handhelds from talking to each other, but if the repeater is on the top of the hill, it can relay the messages between these two handhelds that might not normally be able to hear each other.

462.550 462.575 462.600 462.625 462.650(1) 462.675(2) 462.700(1) 462.725
(1) Use not permitted near Canadian border.
(2) Nationwide emergency and road information calling. Nationally recognized coded squelch for repeater operation is 141.3 Hz.

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