ICOM F21GM Scanning Problem/Question

[MikeSD]

I have two barely used F21GM Radios. They are excellent GMRS radios and work great. I have tested both of these on all channels, with and without tones. They work great. There is one problem I'm experiencing on both radios. And both radios behave identically.

The problem: When I put a radio on ch16 (scan), the radio will scan, the light blink during scan, and when there is any signal, it stops, until the signal disappears and then continues scan. The problem is, most of the time all I hear is a continuous sound that sounds like unsquelched noise (I.e. The sound you get when you push moni, with no signal). Occasionally, there will be this brief noise, followed by silence. And once in a while it will work as I expect and I can hear the audio.

I have tested this scan using multiple other radios transmitting, and both of these F21GM behave identically as described above. This question is for those who have, have used, or know what might be causing the scan to work like this. What might be causing this behavior?

Any ideas? I suppose they could both be identically broken, but for now I'm thinking I just don't understand something about this mode. There are only about 2 sentences in the manual on scan.

 

[Quickcall]

If you have the software try adjusting the squelch.

 

[MikeSD]

If you have the software try adjusting the squelch.

I think it's just the opposite of a squelch problem. The problem is that I can't hear the audio part, although I can hear the carrier noise. However, it might be a related problem.

I have done some further investigation and think my problem might be that when I test the radios, I'm using other radios I have. And those radios are only a couple of feet from the receiver. I think it might just be too strong of a signal and it might just be swamping out the receiver.

When I scan the channels and wait for other people's transmissions, the radio seems to work ok. It's just that I can't get the audio reception, when I'm withing a few feet of the receiving radio.

 

[SkipSanders]

The F21GM isn't 'officially' computer programmable. The software for the F21 (not GM) will work, but only if you know how to put it into 'manufacturing' mode, otherwise it will refuse to recognize the radio.

You need the Icom CS-F11 software, the correct cable, and the seeeekrit code. <grin>

The only reason to use it is if you need to program in split tones, though.

 

[MikeSD]

You need the Icom CS-F11 software, the correct cable, and the seeeekrit code. <grin>

The only reason to use it is if you need to program in split tones, though.

And it would be helpful for programming tones for the channels. The button method requires pressing 3 buttons, simultaneously, while turning on the radio. It's a bit tricky and when you have to do this on 15 channels on two radios, that's a lot of finger fatigue.

I guess I'll have to look around for the software (unless someone wants to tell me where it is) and hope someone will give me the super secret code.

 

[bezking]

OP,

Asking for software is not permitted here.

Thanks!

 

[dwh367]

I think it's just the opposite of a squelch problem. The problem is that I can't hear the audio part, although I can hear the carrier noise. However, it might be a related problem.

I have done some further investigation and think my problem might be that when I test the radios, I'm using other radios I have. And those radios are only a couple of feet from the receiver. I think it might just be too strong of a signal and it might just be swamping out the receiver.

When I scan the channels and wait for other people's transmissions, the radio seems to work ok. It's just that I can't get the audio reception, when I'm withing a few feet of the receiving radio.

I think you have found your problem. With the frequency spacing being so close, it would be very easy to desense your receiver when transmitting near it. It can stop on an adjacent frequency instead and cause the symptoms you are describing.