Anyone else have issues with scan not stopping on signals?

[kt4lh]

I was traveling for the holidays and was parked on the interstate for two hours because of a wreck so I was doing a bit of playing with radio.. I had the GD77 scanning FRS (for rx only, just to hear if anyone was talking) and heard nothing for several minutes, then I stopped it scanning and coincidentally stopped on a channel where there was someone talking and their signal was strong and there was a QSO going on, happened to be a GMRS repeater. I started scan again out of curiosity, nothing. Stopped and went to that channel again, same back and forth QSO.

Their signal was quite strong, clear, and I can't think of any reason scan wouldn't have picked it up. Sure scanning will miss periodic transmissions, but I've used a scanner since the 80s and ham radio since the 90s so I am pretty aware of the limitations there. It just seems the GD77 wasn't hearing them at all? The zone I was in had FRS and GMRS in it, so a total of 22 channels, so I'm sure there's no way it just happened to be missing every transmission.

I'm on the Nov 2 2022 firmware, ced2604. I know there have been two updates since this which I hadn't updated to yet, but neither indicate anything related to scanning.

I hadn't looked until today in settings; I found a Scan Dwell setting which, as far as I know is at default at 30mS. I would have tried increasing this time. Is 30mS default?

[G4EML]

You are correct, scan dwell time is the amount of time the radio listens to a channel before it decides that there is a signal or not.
30ms is the default and gives the fastest scanning speed, this has been found to work reliably on most radios.
However it may be that your radio needs a little longer to detect the signal, in which case you may need to increase the dwell time.

Colin G4EML

[kt4lh]

You are correct, scan dwell time is the amount of time the radio listens to a channel before it decides that there is a signal or not.
30ms is the default and gives the fastest scanning speed, this has been found to work reliably on most radios.
However it may be that your radio needs a little longer to detect the signal, in which case you may need to increase the dwell time.

Colin G4EML

I've been experimenting with my two GD77's here... I know that each radio may differ slightly, but... Put one on 120 and one on the default 30 and so far both seem to stop similarly :/ I"m not sure what was going on the other day, there's no reason it shouldn't have been stopping. Oh well.

I very rarely scan on these radios, may just set 'em both to 120mS or something and hopefully avoid an issue.