San Diego RCS, bc296d, and Audio Quailty

[chuckinsocal]

Hi Gang,
I monitor the San Diego RCS North Zone exclusively. The vast majority of the digital transmissions are crystal clear, however some digital transmissions are garbled, choppy, sound like someone talking into a barrel, have electronic background noise, or have other quality issues.

So now a few questions:

Has anyone found the optimal audio quality settings for the 296d on the San Diego RCS and if so could you share them? I've tried several settings but can't get rid of the problem. The manual says that the lower the quality setting the better the sound quality so I'm now at 333. It seems like the longer the transmission, the greater the chance that the sound quality will deteriorate.

Are there any other settings I should be looking at? I once had a squelch setting issue but that has been resolved. I recently upgraded my firmware to the latest with the rebanding capability and sound quality has improved but it has not totally eliminated the problem.

Or, are these occasional audio quality issues just inherent in P25 transmissions and I just have to learn to live with them?

Thanks in advance for any wisdom you can share.

chuckinsocal

EDIT: So I was just reading about simulcast systems in the wiki and maybe that is the root of the problem. I'm about 4 miles from one tower with direct line of sight and about 2 miles from another tower with no line of sight. Maybe one tower site occasionally interferes with the other?

 

[chuckinsocal]

So, no one has any wisdom to share?

 

[flugpop]

Not for that scanner. It seems when I monitor Trunked systems with P25 I have the most problems. I can pick up conventional P25 transmissions’ with little to no signal full quieting. I’m still trying to figure this out to.

 

[code3cowboy]

The vast majority of the digital transmissions are crystal clear, however some digital transmissions are garbled, choppy, sound like someone talking into a barrel, have electronic background noise, or have other quality issues.

If you find a solution let me know please. Some of the transmissions I hear are crystal clear, but many are garbled, choppy, and sound like someone talking into a barrel.

I should mention I have this problem at work and am not using a scanner. HAHAHA

 

[WayneH]

From my experience monitoring the RCS it's more due to either a phasing issue when monitoring the North or South Zones (because they're Simulcast) that revolves around terrain causing out of phase conditions or it's because the equipment isn't properly calibrated/maintained. Simulcast systems be they analog or digital have to have preventive maintenance done more regularly because of this. The County may not take this in to consideration.

 

[chuckinsocal]

Here's an interesting little tidbit: I bought my scanner used about 6 weeks ago and because I didn't receive the cable I programmed Bank 1 manually along with the talk groups. Never even looked at any of the other banks.

So I received the cable the other day and decided to down load the banks and TGs to my computer. I found various freqs and TGs in some of the upper banks, deleted them all, and reuploaded just my Bank 1 and TGs to the scanner.

I have no idea why, how, or what the connection might be but since then my sound quality has improved significantly. I still get an occasional fail but they're rare, maybe once a day or even less.

So, I'll just chalk it all up to phasing, interference, or other inherent system or P25 issues I can't do anything about. Thinking back to the old VHF analog days, there were bad transmissions then too so it's probably no worse today. I'm gonna put the issue to rest.

Thanks for all your comments.

chuckinsocal

 

[flugpop]

Today I took my 396 up to a hilltop in Temecula that I work at and I was able to pick up the North system and the P25 was horrible with full signal, attenuator didn't even help. The analog sounded pretty good. So I think its a mutipath/simulcast problem too.
San Diego City sounded great.

 

[W6KRU]

That's great Chuck. I am glad you got that sorted out.

 

[brandon]

I have a ProScan controlled BC796D located in El Cajon and the RCS North sounds terrible! The signal jumps from 0-5 bars and can be quite scratchy. A few months ago the RCS North could be received at full scale from the same location in El Cajon. Antenna is an 800 MHz yagi. As I just put the radio back Friday night, did not have an opportunity to check the antenna/connectors. The San Diego City and RCS South systems continue to be received at 100% quality however.