BCD396xt Audio Delay

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W4TF

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AJ4VS, it sounds to me like the problem is that the P25 Waiting Time is set to 100 ms or higher on the site(s) that you are trying to monitor. This would cause the exact problem that you are describing. RickLeb mentioned that you should look into this possibility in his earlier post, but I didn't see you (the OP) address whether or not you verified that the P25 Waiting Time is definitely set to 0 ms on each site that you are monitoring. Even if you think the P25 Waiting Time should not be a problem since the audio is set to analog only, you should still check out what the P25 Waiting Time is set on for each site in the system that you are having problems with to ensure that is not your problem.

When I program a site for a trunking system that is not a pure P25 system into my BCD396XT, the P25 Waiting Time is always set at a default of 400 ms for each site. This delay of 400 ms will always cause a delay in the audio because the scanner will wait 400 ms to try and detect a P25 signal (even if you are monitoring an analog system) before any audio will be heard. I always turn the P25 Waiting Time to 0 ms to prevent the exact problem that you are describing. You should definitely check to ensure that your P25 Waiting Time is set to 0 ms, which will ensure that there is no delay in allowing you to hear audio. The P25 Waiting Time can be changed by selecting a site in the system that you want to change the P25 Waiting Time for and scrolling down the menu until you find the P25 Waiting Time option, then simply set it to 0 ms. You will have to make that change for every site in the system that is giving you problems.

I have a strong suspicion that the P25 Waiting Time is set to 100 ms or higher (it's probably set on the default 400 ms) on each site that is on the system that you are experiencing problems with and that setting the P25 Waiting Time to 0 ms will fix your problem. I hope this helps you and I wish you the best of luck in trying to fix your problem. Let us know if this turns out to be the problem.

I checked and you are correct, the p25 setting was not at 0. I changed to 0 like you said. Unfortunately, the problem still persists. I really like the features and size of this radio, but I'm starting to feel discouraged in using it. I really don't want to, but it seems like my pro-106 is still going to be my daily radio :-(
 

Avery93

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All of the Uniden scanners I've owned (BCT15, 346XT, 996XT) have had slow tone decoding speed, compared to GRE scanners and commercial Icom and Motorola radios. I have always set the correct modulation, and it occurs regardless of signal strength or any interference present. It is sometimes bad enough that I entirely miss short transmissions on my Uniden, whereas another radio will catch it with no noticeable clipping.

Another problem with delays I have found recently is with "P25 one-freq-trunk" systems, which are necessary on Unidens to decode Radio IDs on conventional P25 channels. Even when holding on a talkgroup in such a system, there is a large delay, probably over half a second, before the audio unmutes. Sometimes however it will not unmute at all, and just flash the signal strength indicator every second or so. I have no problem receiving this system when setup on a normal channel with audio type set to "All" or "Digital only".

To thomast77: You can find out what modulation an agency is using by going to their RR database entry, clicking on the callsign and looking at the "Emission" column. 20K0F3E and 16K0F3E are wideband (FM), and 11K0F3E or 11K2F3E are narrowband (NFM). If both are present that agency may be in the process of converting to narrowband, or has already converted. You can find a more complete listing of emission designators here.
 

thomast77

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To thomast77: You can find out what modulation an agency is using by going to their RR database entry, clicking on the callsign and looking at the "Emission" column. 20K0F3E and 16K0F3E are wideband (FM), and 11K0F3E or 11K2F3E are narrowband (NFM). If both are present that agency may be in the process of converting to narrowband, or has already converted. You can find a more complete listing of emission designators here.

They have both designators. I have added all the tones back and changed from nfm to fm. And although I have noticed some improvement. There are still occasional delays and missed transmissions. So it has helped to change to fm. Any other ideas on what other settings can be changed?
 

W4TF

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my system is narrow FM, but just out of curiosity, I'll switch to FM to see what happens...
 

jackj

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I would be very surprised if changing from Narrow FM to FM has any effect on PL decoding speed. There is no reason for a change in modulation from NFM to FM to effect anything other than the de-emphasis and audio gain. The PL tones should be sampled before any de-emphasis is applied to the audio. It would be nice if the IF bandwidth changed also but I don't believe that happens.
 

W4TF

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I agree with you 100% that it shouldn't make a difference. however, at this point i've gone past logic and working via desperation :)
 
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