EDACS beeps on Richmond trunked system?

[hanta]

Hello,
I've been listening to the Richmond trunked system for about a year and some time ago began getting the EDACS beeps following transmissions on the 8th frequency, 860.7125. See attached zip file for a sample. I've had one other person tell me they have no trouble with this system. I'd like to figure out how to troubleshoot my setup, or if this is something inherent to my radio or the trunked system. Anybody with advice?

I'm using a Uniden BR330T, with the system programmed as EDACS/WIDE, here are the channels:

0866.1000 1
0866.7500 2
0867.1000 3
0867.6250 4
0868.6125 5
0867.8750 6
0858.7125 7
0860.7125 8


The other EDACS/WIDE system I listen to is BART, and I don't get the beeps. It'd be nice to fix this so I'm not listening to so many beeps.
Thanks for your help!

...beep...beep...beep...beep

 

[WayneH]

It's got to be an alignment issue with that repeater since I seem to recall it being added a while back. The scanner's tolerances must be tighter than the other scanners not having issues or they use an alternate means to 'disconnect'.

 

[PocketProtector]

Richmond EDACS Beeps

Hello Wayne,

I too have those beeps showing up on my BC246T. On some but not all calls -- I am not clever enough to diagnose why the beeps appear on some, but not all calls.

Anyhow, what do you think about just eliminating 0858.7125 7? Would that also get rid of a good number of calls? Forgive me for asking what might be a lame question (or something I suppose I could just try and see what happens -- but then wouldn't know if I was missing something anyway).

Thanks
Steve

 

[linuxwrangler]

The beeps started after their system upgrade when they added some channels. There were at least 2-3 threads about them. It's only the one channel that has the different "harsh" sounding beeps. I don't know enough about EDACS to know what the standard requires - perhaps they are within standard and the scanners can't deal but I suspect the system is a tad screwed-up. Doesn't appear that the field units are affected by this though they have a number of other complaints.

If you eliminate that frequency, you will miss about one in 5-7 calls. Right now you are only missing the ones that get stomped on by the beeps.

It would be interesting to see what any of the scanner engineers have to say about them after listening to your file or the ones I posted way back.

 

[zz0468]

It might not be an alignment problem so much as something in the firmware for the 'getc' associated with that radio. In the EDACS system I was involved with, every major firmware revision seemed to come with it's own unique set of noises it would create at the end of a transmission. In 1992, they even played the old 'GE Jingle' at the end of every transmission.

Since I was the transmission engineer (microwave) and didn't dive too deeply into the 800 radios at the time, I never had the opportunity to get a straight answer as to the purpose, other than the GE Jingle was intended to thwart scanner listeners.

I've heard similar beeps, sine wave beeps of much higher frequency, dtmf-like tones, and the GE Jingle coming from EDACS systems. There really is no standard when it comes to these beeps... the disconnect word is contained in the low speed data sent on every voice channel, so the EDACS user never hears this.

 

[WayneH]

the disconnect word is contained in the low speed data sent on every voice channel, so the EDACS user never hears this.

Right, which when the transmitter needs a full alignment can affect transmit of the lowspeed. This can be seen on LTR systems occasionally when monitoring with scanners.

I'd guess Richmond contacts their communications out to Day Wireless or some other piss-poor private comm company who generally know nothing about trunked infrastructure other than what their salesmen recommend.

 

[linuxwrangler]

Recent city-council meeting might have clues:

December 2007:
DISCUSS & CONSIDER: recommending a sole source purchase of 800 MHz
public safety radio equipment from Dailey-Wells in an amount not to exceed
$473,359.27. - (Police Department) Chief Chris Magnus 620-6655.

June 2008:
DISCUSS & CONSIDER: approval of a sole source purchase of a two-year
standard maintenance agreement with MA/Com, the original equipment
manufacturer for the 800 MHz Public Safety Radio System, in an amount not to
exceed $1,147,604.55 – (Police Department) Chris Magnus, 620-6656.

 

[cousinkix1953]

The LAPD has the same kind of beeps on their radios too. I hear this when watching COPS...

 

[WayneH]

The LAPD has the same kind of beeps on their radios too. I hear this when watching COPS...

That's called MODAT and was used for radio identification. Since they switched to digital long ago it is no longer used or compatible.

 

[brandon]

Hello. Sorry to dig up this old post but I was reading this thread and am curious if Richmond ever resolved this beeping issue on the EDACS system? I have the same problem down here while monitoring Riverside County (since Nov 2008). Just like your system, it only happens on one channel, the other frequencies are fine. As its been a few months I'm afraid the "bad beeps" are probably here to stay, but wanted to see what others have experienced with Richmond (since your beeping problem started a lot sooner than ours).

I have a PSR-500 which is able to handle these rough beeps and track just fine, but all of my Uniden scanners cannot track properly due to it. It's a no go for RadioShack models too (except the new GRE clones).

 

[zz0468]

I have the same problem down here while monitoring Riverside County (since Nov 2008). Just like your system, it only happens on one channel, the other frequencies are fine. As its been a few months I'm afraid the "bad beeps" are probably here to stay, but wanted to see what others have experienced with Richmond (since your beeping problem started a lot sooner than ours).

I'd be real curious to know which system and channel you hear that on. Have you tried listening to all the channels in conventional mode? Generally, the beeps are always there, in some form or another. But it could validate Wayne's theory that an alignment is needed. There's a turn off code embedded in the low speed data that tells a radio to mute when a transmission is done. Miss that turn off code, and the radio reverts to carrier squelch, so you hear all the burps and belches and beeps the system makes that were never intended to be heard.

 

[brandon]

Good morning zz:

This happens with West Ch 03 (866.7125). Here is sample audio of the harsh beeps.
All the other systems appear to be fine as far as I can tell.

-Brandon

 

[linuxwrangler]

Yup, those sound just like the beeps on the Richmond system. I should note that it is not just a scanner issue. I was chatting with a couple officers at the local coffee shop last week and heard them on their radio. They grumbled a bit about the state of the radio system.

 

[zz0468]

Good morning zz:

This happens with West Ch 03 (866.7125). Here is sample audio of the harsh beeps.
All the other systems appear to be fine as far as I can tell.

-Brandon

Good evening, Brandon.

If that's the only channel doing that, the odd thing is that it's just that one channel. Those beeps are typical EDACS, and the specific tones generated seem to be tied to specific firmware versions on the GETC boards associated with each individual channel. Since that's a simulcast system, the tones are probably being generated at the control point. I've heard DTMF like tones, high pitch, like 3 KHz tones, and beeps like your recording.

When that system was first put in, it actually played the GE jingle (we bring good things to life!) at the end of EVERY transmission. Apparently, that particular GETC board is different than the rest. It's not inconceivable that it could even be an older rev firmware installed as a replacement to a failed board.

You WILL hear it in conventional. If you hear it while trunked, you're missing the turn off word in the low speed data. That DOES happen occasionally, even on real radios. I drove around with an EDACS radio for years, and would occasionally hear the jingle. I suspect that the low speed deviation is a bit low from what really works. It's not out of the question that the level could be low on one channel, and fine on the rest, or even low on one transmitter out of the batch in the simulcast system.

If there are channels that DON'T have it, they were simply programmed that way. Like I said in a previous post, there never really was a straight answer as to why, other than to thwart scanners a bit.

 

[brandon]

zz: Thanks for the interesting info.

Since the newer PSR-500 scanner doesn't stumble on those harsh beeps, I wonder if this can be fixed with a scanner firmware update. I'll pop the question in the Uniden forum and see what Paul has to say. A long shot but worth a try I suppose

Thanks again.

-Brandon

 

[vince48]

Hey Guys,
Can anyone in Hayward monitor the Richmond system? I can hear the CC and the other frequencies sometimes, but I just can't seem to track.