Page 1 of 1
Astro/digital sq question
Posted: Wed Jan 08, 2003 8:53 am
by Aragorn
We recently had our local municipality move over to an Astro trunked system using XTS3500 and Astro Spectras. They are using Astro mode all the time, but no encryption. Now, the question is, I programmed my A/S 3 for their freqs using conventional (non-trunked) channels, since I don't have the trunked info anyway, and set each channel (5 of them) to Astro with digital squelch. I conventionally scan the 5 channels bu I get very intermediate digital noise\sounds and that's it. I don't hear anyone talking or anything else. What\how do I set up my A/S to only hear them without having the trunking or Astro info? Thanks.
digital mod. type??
Posted: Wed Jan 08, 2003 3:55 pm
by CHEFA2001
Do you have a VSELP or IBbE radio? What type of system are they using, the two are not comaptible w/ each other. Just a simple thought.
Posted: Wed Jan 08, 2003 4:03 pm
by wavetar
I assume you have an IMBE radio since Digital CSQ is not a feature of VSELP radios. Is it a simulcast system? If so, their radios will be set for either digital type "CQPSK", for narrow-band or "Wide" for wide-band operation. The default digital type is C4FM, found on the same screen that you set the Digital CSQ. Try them all if you're not sure. Hope that helps. BTW, you'll hear any & all digital & trunking info regardless when scanning conventionally, no way around that.
Todd
Posted: Thu Jan 09, 2003 7:39 am
by Aragorn
I don't know much about the system except what they're using radio-wise and that they're running Astro all the time, non-encrypted. I know I'll hear everything, but that's ok. I only want to monitor them. I'll try the different digital types and see if that works. Thanks guys.
"Digital Carrier Squelch Network ID"/Distorted Rec
Posted: Thu Jan 09, 2003 9:54 pm
by nylawman
1. I recently purchased a rebuilt Astro Saber III (eBay) and the latest Motorola Astro Saber/Spectra software and updates (from Motorola). I am a law enforcement officer whose agency currently uses analog equipment but I purchased the Astro so I can monitor (receive only) neighboring departments who use digital systems.
I was told that Network ID 293 (or 273??) is the equivelent of "CSQ" in an analog environment and that by programing the Network ID as such, I would be able to monitor that agency (non-encrypted). Whenever I do, however, all I get is a flashing red incoming carrier signal until I depress the "monitor/open squelch" key.
Is there any way I can get this audio to come thru without watching for a flashing indicator and manually depressing the monitor key?
2. The radio I purchased had several test frequencies programmed in the upper T-band (500 megs). The receive frequencies I programmed range from 453 to 477. The audio on the analog 453 freqs is choppy and clearly inferior to my analog Bendix King. Isn't the Astro Saber 450-512 truly broadband? Is it possible that the radio was "tuned" for the upper T-Band?
Posted: Fri Jan 10, 2003 10:17 am
by Aragorn
NYLawman, yes, it is possible but if that was the case the radio wasn't properly tuned then because it should be able to hangle the 450-512MHz that it's spec'ed for.
I'm still at a loss here. I can't seem to hear anything but intermittent digital noise. I'm using the digital CSQ setting and I've tried all three digital types, C4FM, cqpsk, and Wide but nothing seems to make a difference. I have noticed that with C4FM or CQPSK I get digital noise but with Wide I get virtually nothing. What else do I need to change? Thanks.
Digital CSQ Cod
Posted: Fri Jan 10, 2003 10:40 am
by nylawman
What is the Newtork ID for "Digital CSQ"; 273 or 293??
Re: Digital CSQ Cod
Posted: Fri Jan 10, 2003 10:51 am
by wavetar
nylawman wrote:What is the Newtork ID for "Digital CSQ"; 273 or 293??
I think there was a misunderstanding. When you set the radio for Digital CSQ, it will set the network parameters to the factory default of 293. But understand that just setting the radio to 293 will not cuase the radio to be in Digital CSQ mode. You must change the "RX Unmute Rule" in the conventional personality (F4->F6->F3->F9->F6 from main menu) from "Normal Squelch" to "Digital CSQ".
Aragorn, I don't know what to tell you without seeing your set-up & system information. Are you sure they're not encrypted?
Todd
Posted: Fri Jan 10, 2003 11:17 am
by Aragorn
Everything else is setup correctly but I've never tried listening to an Astro system before so regarding the Astro/digital settings I'm slightly at a loss. Except for the Digital CSQ and the digital type settings, what else needs to match for me to hear them using non-trunked means....besides the freq, etc.?
PS, I've just been told the system is running ASTRO 3600 baud. Does this matter just to monitor them?
Posted: Fri Jan 10, 2003 2:17 pm
by 515
NAC code F7E (hex) / 3966 (decimal) was supposed to be the equivalent of "Digital Carrier Squelch", meaning you should be able to program this into any P25 radio, and have it unmute for any NAC.
Motorola radios generally don't support this special NAC, though. You can program a channel with it, but it will behave just like any other NAC. If you want to hear all digital traffic with a Motorola radio, you have to use the "Digital Carrier Squelch" option in the RSS/CPS.
The EF Johnson P25 radios generally support this special NAC. I beleive the Racal 25 Portables also do.
Posted: Fri Jan 10, 2003 3:24 pm
by wavetar
Aragorn wrote:Everything else is setup correctly but I've never tried listening to an Astro system before so regarding the Astro/digital settings I'm slightly at a loss. Except for the Digital CSQ and the digital type settings, what else needs to match for me to hear them using non-trunked means....besides the freq, etc.?
Nothing that i'm aware of, that's why I'm confused too.
Aragorn wrote:PS, I've just been told the system is running ASTRO 3600 baud. Does this matter just to monitor them?
Not for monitoring them with the method you are using. How new is this system? Perhaps they are VSELP?
Todd
Posted: Sat Jan 11, 2003 7:07 am
by Aragorn
They went into ops about March of last year and are using XTS3000's and Astro Spectras. I have nothing further to go on. Edit: I thought my buddy had a VSELP A/S3 but he's got what I have.
Anyone have a codeplug for A/S3 uhf-hi with VSELP and CAI?
Posted: Sat Jan 11, 2003 3:03 pm
by wavetar
Aragorn wrote:Anyone have a codeplug for A/S3 uhf-hi with VSELP and CAI?
No go. Two completely different digital protocols with incompatible hardware. It's either one or the other. What system is it? Perhaps someone here can verify what type it is.
Todd
Posted: Sat Jan 11, 2003 4:55 pm
by Aragorn
Edison, NJ. I thought it was either VSELP or IMBE? I checked my old A/S since and it is VSELP but doesn't do CAI. I figured if I got a plug with the same split with CAI I could somehow get it into it. The new A/S I have is the one with CAI but it's IMBE and has a much newer Host and DSP.
Posted: Sat Jan 11, 2003 5:13 pm
by wavetar
CAI means Common Air Interface, and IMBE is the digital protocol used for it, as part of the Apco-25 specifications. So, no VSELP CAI radios exist.
Todd
Posted: Sat Jan 11, 2003 7:52 pm
by Aragorn
Are VSELP radios still being pushed by Motorola? I surmized the IMBE/CAI radios are being touted as the lastest and greatest so they'd get that. If they are VSELP then the only way to monitor them would be with a system key and properly setup radio that matches their programming...?
Posted: Sun Jan 12, 2003 8:35 am
by Aragorn
Thanks Shaun. I didn't plan on trying to change my new A/S, however the old one has been thru the mill already. Frankenstien, I call it.

It's been flashed with the "infamous" plug. I checked the flash of the old radio before and I believe it won't do Apco25. Here's the specs:
A/S3 #1(new): R7.08.00, DSP N08.02.02, H04SDH9PW7AN, 1MB, 591008-4F1E00-9
A/S3 #2(old): R05.00.02, DSP 06.04.09, H04SDH9PW7AN, 1MB, 840101-8FFF00-5
Posted: Sun Jan 12, 2003 8:40 pm
by Aragorn
Shaun, the thing is is that I get very little of anything. From the little I've heard and comparing it to your mp3 I think they are encrypted. I hope I'm wrong.
Posted: Mon Jan 13, 2003 7:36 am
by Aragorn
No, I'm not, however I have freinds who are. I'll have to see what we can do. Thanks.
Posted: Thu Jan 16, 2003 10:40 am
by willbartlett
Here's a dumb question. If I were to add a display to my AS-I and power it up while holding the ".." button, would I get the host/dsp/etc. on the screen? Is this a function supported by the controller at a base level or is it part of the codeplug and/or s-record info contained in an AS-II or III level codeplug?
Thanks, Will
Edison, NJ
Posted: Thu Jan 16, 2003 12:04 pm
by ASTRO_25
The latest word that I have received on the Edison NJ system is that all Police Operations on this system are APCO-25 Digital with DES-OFB.
Latest Info at:
http://www.trunkedradio.net/modules.php ... DB&sid=757
Thus, you will not be able to monitor any of the Police Communications on this system unless you know someone in the radio shop who will load the DES-OFB Key into your radio.
Good luck!
Lindsay
Posted: Thu Jan 16, 2003 2:47 pm
by Aragorn
Thanks Lindsay. Actually, my buddy put those last entries on the Trunked Radio site for the Edison system. He has confirmed they are running DES-OFB like you say. I've decided to not even try to pursue securing a system key. I don't want any hassles over it.
Posted: Thu Jan 16, 2003 3:06 pm
by wavetar
Well, mystery solved anyway. A system key wouldn't do you any good. You'd still need the proper encryption key to hear the DES-OFB encrypted traffic, even with the radio programmed onto the system.
Todd
Posted: Fri Jan 17, 2003 7:01 am
by 515
While receiving P25 transmissions on this system in question, watch the red busy LED on the radio. If it double-blinks (blink-blink....blink-blink...), you are receiving an encrypted signal. If it is the normal blink (blink...blink...), the signal you are currently receiving should be in the clear.
Posted: Fri Jan 17, 2003 8:22 am
by Aragorn
Right, Todd. I meant the encryp-key. 515, thanks for that. I didn't know that. We definitely know they are 'crypted now, though.