Vic20 PMR Radio tester

Download: (zipped .prg)

This program was made for testing PMR radios. PMR stands for Private Mobile Radio and is a standard for license free walkie-talkies in Europe. It's an open free standard so that different brands of walkie talkies can talk to each other. It has 8 different channels and often 38 sub codes on each channel. The maximum range is about 3km. (But I have reached 5.2km in a very flat terrain). Anyway... I wanted to test how far they reached (by myself) and that's why I wrote this little program. For it to work, your PMR radio must have a VOX function (that you can set it so start sending the second you start to talk). The program just plays a ~15 second sound (and a quite funny one) in an user specified interval. I used 300 seconds (5 minutes) and started the program exactly on an even five minute point in time so that I would know that the radio started to send every 5, 10, 15, 20, 25 minutes etc...

So just start the program, put one radio on VOX in front of the TV and turn the volume up enough that the VOX function works and walk away with the other radio or take a bike or whatever... But I noticed that having the radio too close to the TV interfered with the signal. Instead of just sending on channel 5 (that I had set it to) I also got the same signal on channel 1. (It doesn't seem to be the vic that interferes, but the TV). So to solve this, I took a pipe/tube of about one meter and put it between the TV speaker and the radio (to lead the sound) and I also angled it off so that the radio wasn't straight in front of the TV. That helped.

Note: This program can of course be used to test any kind of walkie-talkies (and not only PMRs) as long as they have a VOX function.

General PMR tips: Hold the radio absolutely still when you send. That helps the reciever when you are far away. While listening, move the radio around a bit very slowly. That helps you to find the best position for a clear sound. Then hold it still there. Just centimeters can make a big difference. Also try to angle the radio differently. You can use the monitor button while you do this to avoid unwanted breaks in the sound.