Clean up Audio on 996XT

[webstar22]

996XT monitoring the Ontario Fleetnet
The tower is 50KM away, I get 3 bars and it's P25 digital.

I've attached a sound file of what I am hearing, sometimes it is 3 bars and clear audio and sometimes 3 bars and the attached sound. Also I get the odd burst of control channel sounds.

Any setting on the 996 that I can adjust to clean this up?

 

[rdale]

The only setting you can adjust is an important one.. Get closer to the tower. You aren't going to hear digital well at that range.

 

[RickLeb]

It sounds like your squelch may be set too high.

 

[rdale]

Isn't that a trunked system? Squelch has no bearing on that.

 

[Danny6569]

Audio

3 bars is plenty to hear the system, make sure youre squelch is on 3, and then make sure you have the talk group ids set up as digital only, try this and see what happens

 

[rdale]

Again - 50km is a LONG way from the tower to get digital.

And to clarify - the squelch setting has NO IMPACT on trunked systems.

 

[UPMan]

Squelch setting will impact all reception, whether trunked or conventional. In order for the scanner to recognize that a frequency is in use, the incoming signal must be higher than the squelch threshold. If squelch is set high, then a marginal signal will cut out (even on a trunked system...where it will also then return to the control channel). If it is set too low, it will fail to leave the channel when the transmission is over (even on a trunked system...especially if end code is missed or end code detection is disabled).

 

[rdale]

Too late to edit my reply

At 50km away, his squelch setting is not why the audio is dropping out.

 

[UPMan]

I agree. Just didn't want someone reading this thread to ignore squelch setting when diagnosing issues, even with trunked. Here are the specific symptoms of poor squelch setting on a trunked system.

Scanner jumps to the voice channel, then jumps right back to the control channel w/o ever providing voice (can actually bounce back and forth multiple times). This will happen if the control channel's signal breaks squelch but for some reason the voice channel does not. To fix this, you would reduce the squelch setting on the scanner so that both the voice and control channels "break squelch."

More commonly I've heard: Sometimes when the transmission is over, I hear open squelch noise or some comms other than the channel I was monitoring. This is usually a combination of having both END CODE DETECT set to OFF and having the squelch set too low (but can even happen with END CODE DETECT se to ON if interference causes the end code to be missed). Solution is to increase the squelch setting.

Less frequently: It takes a long time to scan a trunked system. If squelch is set too low, the scanner will spend a lot of time trying to determine whether the frequency is control channel data before moving on to the next frequency (it is normal for it to do this for every channel that breaks squelch, but typically this isn't every channel in the system at once...).

 

[Danny6569]

Audio

When i listened to his audio it sounded a lot like my little digital tvs audio when im driving, i have a 3.5 inch digital tv and i tried listening to it while driving and it was real choppy like his is, like it was all breaking up and stuff, i have the 396 xt here and also the 996 xt radio and even when i dont get many bars i still get good audio though, i have all my squelchs settings on 3 and i make sure the audio setting are all set to digital only, i wonder if that would be his problem ? if i was him i would check the audio settings and the squelch and also try putting up a roof antenna, if that dont work then im lost ?

 

[Bote]

That recording snippet sounds like the BER (bit-error rate) is too high. This could be caused by weak signal (regardless of how many bars it shows), interference from nearby transmitters, or maybe there is a magical hidden setting in the 996XT that can improve decoding performance.

Come on AMBE+2, can't get here fast enough!

 

[Gigs17201]

Hi.

I have been doing some extensive research about a problem that I am having that almost matches this same situation. I chuckled that their is this "active" topic regarding the same cause. I am asking for some additional help regarding this scenario.

Our County is switching over to this new Motorola Smartzone P25 System. Their are (2) two sites in the system (this info is also listed under Franklin County, PA Trunked System). Anyway, their is a "Site 101" with SIX UHF-T Band frequencies and a "Site 102" with SIX additional UHF-T Band Freqs.

Anyway, I am located in this County.... actually in the Center of the County with FULL Signal bars. I get the same results whether using indoor antenna or outside antenna. Because this whole P25/Digital thing is new to our entire area..... as its been all Lowband Conventional before this, is all new to myself and many others around here.

I have the Uniden BCD996XT (2 of them actually.... one in car and one in home connected to computer). I purchased and use PROSCAN which allows remote control of scanner, and I also am continuously recording the audio.

I have searched and read about doing this/and that for Trunking optomization, etc. but nothing has worked. The audio breaks up, cuts out, etc. (now its not as bad as the OP, but it defiantly isn't right and don't want it to remain this way forever). I have no idea what to do to fix it. I did read about turning scanner off, then back on while holding Volume button and get into "settings" and make an adjustment to P25 Level stuff, but that didn't seem to help.

I'm confident there is some setting, that is off and needs aligned..... not Squelch cause thats not the problem.... besides already tried that. I'm thinking more along the line of Bit Rate Adjustment or something that could adjust some type of levels for P25. One thing to mention if it matters or helps. Radio Reference freqs show a "Control Channel" freq for both sites (but this seems to change from time to time by observing the scanner). I don't know how to "assign" a Control Channel as ProScan doesn't really show anything such, but maybe that doesn't matter anyway..... maybe the scanner don't care cause it finds Control Channel by itself.

Please help provide some ideas or solution to "Optomize" the P25 Level. Other than that, the new system will be awesome when completely in use (PS: my portable and mobile works excellent on receiving the system.... so its not a system defect; just scanner needing aligned or something).

THANKS