LCSA Amateur Radio programming for 2-way radios

evought's picture

In the last week, I have had to try to extend the standard radio layout for our 2-way radios to a model that we have not used before, the Baofeng UV-82HP. This radio is supported by CHIRP, but has some interesting quirks that had to be worked around and the memory layout is 128 channels in 2 banks vs. our standard 200 channel layout. As I am rebuilding and updating our programming, I intend to describe some of those issues here as well as go into why we laid out the HAM channels the way we did in the first place. I am doing this for institutional memory (it was long enough ago that I had to look up the original email discussion myself to remember why we did what we did) and because it might be useful to others. For volunteers, understanding the why of the layout may help you find what you need when you need it (this also tends to be covered in periodic 2-way radio training, but with the blatted virus going around...)

Recap of Basic Layout Issues

As a law enforcement Auxiliary, working on the field alongside a variety of professional and volunteer organizations, we may have a need to communicate with practically anyone with little warning and may end up connecting communications between law enforcement and other organizations, including CERT, ARES, and SKYWarn, or organizations on regional/national interoperability channels in a multi-agency response. Unfortunately, this means we need a LARGE variety of channels pre-programmed on a single handset which can be carried on call, packed into kits, or pulled from a cache and cloned. We can then use more specialized, better-quality handheld, mobile, or base station radios when we can concentrate on specific communication needs (e.g. amateur radio net-control coordinating with ARES or dedicated public service radios).

Most of our volunteers are also amateur radio operators, which also allows them to carry unlocked, field-programmable radios. That opens up the possibility that we can program, test, and clone a new (or corrected) channel on the fly (which we have sometimes had to do), but we want to do that as little as possible for at least predictable needs.

Basically, then, we have a standard spreadsheet of frequencies, starting with public service (local law enforcement, then mutual aid channels, national interoperability) and then getting into other services, some of them listen-only depending on licensing: NOAA, FRS/GMRS, MURS, and amateur radio. The amateur radio channels go well past the 128 channel mark, but there are gaps earlier in the layout (so that interoperability channels actually match their NIFOG assigned numbers).

Issues Specific to this Baofeng Radio.

Baofengs often have an issue where slight firmware changes are made within a particular radio model. This can affect cloning and licensing. You can pick up two UV-5Rs, for instance, one is Part-90 licensed while the other is not and the same pre-prepared image may not work across them both. This can take some care to sort out.

With the UV-82HPs, we ran into one radio in a set of three which could not use the same image generated in CHIRP. The way to solve this is by:

  1. factory-resetting the radio, (menu option for full reset)
  2. download the factory image for THAT firmware into CHIRP
  3. copy and paste the channel assignments from the generic table into the new image.
  4. CHIRP generic comma-separated value files are 0-based whereas most model-specific images start their memory at 1, make sure you copy and paste the correct offset or your channels will be off by one!) An easy way to check this is to make sure that, e.g. VCLL10 is actually channel 10.
  5. Change the settings for the individual radio: you will probably want to set the voice back to English instead of Chinese(!), set initial channels, set band A to display channel name, and B to display frequency (why explained below), and, since you are customizing the radio anyway, setting the name or call-sign of the owner/assignee in the welcome message to easily distinguish radios on the field.
  6. Save the image to a file and Upload to the radio. The UV-82HP does not require any special magic to go into clone mode and automatically refreshes the display when the upload is complete.

In this particular case, we ran into a bug in a daily CHIRP version which corrupted our file, but this was fixed by an update and restore of the file from a backup. It is a good idea to manually sanity check the written image afterwards, walking through the assigned channels and doing a radio check on a low-traffic channel or low-traffic time.

The Amateur Radio Channels

For any region, there are going to be a substantial number of amateur radio channels (repeaters plus common simplex assignments) and, with many radio handsets only allowing 6-character descriptions, it can be very difficult to distinguish them. With linked repeaters, entries on multiple input frequencies can even have the same call-sign. One of our experienced amateur operators began laying them out in frequency order with short location descriptions and then setting the radios to display channel name on Band A, channel frequency on Band B.

This arrangement made it so that we could have a common named channel on the primary display and find channels by frequency on the other (the "970 repeater"). If we need to find a amateur repeater by name ("JOPLIN"), we can jump to the start of the Amateur channels by punching in the number on A, then step through the channels with the arrow key, switching it to B if desired after we find it. Setting the same channel on A and B then helpfully displays both name and frequency. This saves us from having to flip through menu options to keep switching the display between CHANNEL-NAME and CHANNEL-FREQUENCY, which can be a royal pain. On our printed radio reference cards, we don't bother printing all of the channels, just a few critical ones and the start of major groups.

The plus side to this is that rearranging the layout to fit in 128 memories is not hard. We just move the Amateur channels after 111 into the gap before 100 after the interoperability channels. Then we either need to mark up or reprint the reference cards with the new offset to the start of the VHF and UHF channels.

As a consequence of locating major HAM channels by frequency, there end up being a handful of "SIMPLX" channels distinguished only by frequency, the 2 meter FM Simplex channels, for instance. There are a number of decent references explaining how these are laid out, such as (Look at the 2 meter band plan and then at the 2M Simplex Frequencies table further down). Our region uses 20 kHz channel spacing, so our simplex channels start at 146.400 MHz, arranged below and above the 2 meter Call channel at 146.520 MHz. We have a small number of these pre-programmed for 2 meter and 70 cm. If we use these channels in the field, they will usually be listed by frequency. In the unlikely case that we use simplex channels not pre-programmed, we will just enter them manually in VFO mode.


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