TG Bleed-Over ??

[bwhite]

Unfortunately I cannot follow my own advice and Search on this question/problem before posting because I don't know what it's called. Anyway, it seems like every few hours I will hear the PD coming thru (both sides of the conversation) on various FD-only TGs.
Doesn't seem like the PD is doing anything odd (I could see one police-person keying up on the wrong TG but not both and not this often).
Anyway, I thought the sub-audible tones from the control channel directed all of this activity, but, I recall months ago a poster mentioning another feature/tone ?? that acted like another layer on top of that to help ensure discrimination (especially in high radio traffic areas).
I'm far from the nearest trunk antenna (for now) so I didn't think this would be a factor, but, perhaps it is. If someone could tell me what this additional layer of toning or whathaveyou is called I'll try to search on it from there. Thanks.

 

[rdale]

Not sure what layer you are talking about - but if the signal isn't good the radio may misinterpret the talkgroup ID and give you the wrong number for transmissions.

 

[bwhite]

This happens on a 245 and 898.
On the 898 I've usually got 3 or more bars and the voices come in loud and clear.
I vaguely remember something about PL but I don't know.

 

[BoxAlarm187]

A friend has a 796D that will do the same thing. He'll be scanning for hours at a time, and then PD will start coming across the FD TGID's intermittantly. Strange.

 

[brandon]

I've heard this while monitoring the San Diego RCS. Even the units hear it and the dispatch will tell them it's bleedover.

 

[ScanManQSL]

A friend has a 796D that will do the same thing. He'll be scanning for hours at a time, and then PD will start coming across the FD TGID's intermittantly. Strange.

That had happen to me a few times on my Pro96. I was listening to Fire Dispatch suddenly I’m hearing Maryland State Police. I was confused on what was going on.

[EDIT]This is on my side. It’s not like what Brandon is saying that the FD and PD can hear each other bleeding over

-

 

[brandon]

That had happen to me a few times to me on my Pro96. I was listening to Fire Dispatch suddenly I’m hearing Maryland State Police. I was confused on what was going on.

That is a bug in the PRO-96/2096. I have the same problem when I monitor a digital talkgroup. It's almost like the radio doesn't return to the CC but stays on the same freq and therefore picks up something else. It only seems to happen for digital talkgroups above 30000 or so. It happens for me quite often on the San Diego RCS and Orange County systems (when monitoring digital talkgroups only). Drives me absolutely insane on Orange County since something encrypted usually pops up afterwards or when you're monitoring the police and then suddenly you hear some school buses yacking away.

 

[PhilJSmith67]

I've heard this happen on my Uniden BC895XLT for the Kankakee IL Public Safety system at times when tropo-ducting was bringing in MECA from Indianapolis, which uses many of the same frequencies in their trunk. The local voice comm would end on the Kankakee System, but a MECA voice comm would take over. Since the Kankakee system rotates all TGIDs through all of the trunk frequencies for each break in transmission, many times a voice comm would resume from a different Kankakee TGID. Since the scanner was unaware of what was actually going on, it would stay locked on the frequency thinking it was "hearing" the same legit TGID the whole time.

My PRO-95 never seems to "false" from this phenomena like the 895, but it also seems like the PRO-95 needs a more potent signal to hold onto a trunked voice comm than the 895.

 

[bwhite]

Starting to sound like the CC isn't getting checked at times and the scanners just blirt out the next series of com's.
In my case there is almost no other traffic while this is going on, I could more understand if there was thick n heavy traffic.