Batboard

I am dealing with a 6 site simulcast astro conventional CAI VHF system. We have been receiving interference from another user licensed on the the same repeater tx frequency(also astro CAI) about 50 miles away since they installed a repeater. Both agencies are within compliance with licensing power levels and antenna location.
In some parts of our city there radio traffic is received as clear as our own.

In speaking with the other agency it has been determined that we are using different NAC codes. And all our radios still pass their audio.

I've done some experimenting by programming a portable to different tx options to see what our astro spectras would unmute to, and the results were just as I had imagined:
with the spectra programmed to rx astro only; the radio would only unmute on the correct astro signal, with the proper NAC. an incorrect NAC would not pass audio.
same thing when programmed to mixed mode, proper NAC with astro works, proper PL on non-astro works. incorrect PL or NAC passes no audio.

So I thought great!, I'll just reprogram all my radios and my 6 quantars and change my NAC.
because this would take about 2 weeks I thought I'd try a different NAC on an XTL5000 consollete that is known to pick up the other agencies transmission quite well to ensure this theroy would work.
Changed the NAC on the consolette, and while I haven't had time to go sit and listen for the unwanted transmissions, it still opens and passes audio transmitted from our repeaters with a mismatched NAC.

All radios are currently programmed for Astro RX, with a unmute/mute type of: And unmute, or Mute. and an astro rx unmute rule set for: normal squelch.

What am I missing?
can someone offer any insight?

Is the audio of the other agency being passed through the system? What I'm thinking is that maybe you have a quantar or quantars that are set for carrier squelch and is being re-broadcasted through your system.

Of course there is no way to look at the Astro-TAC or listen to the front speaker of the quantar to hear the recovered audio to see this and you may have to go read each individual quantar seperately and evaluate.

the Audio is not being picked up by the receivers and repeated. the frequency in question is being used as a repeater Tx frequency by both agencies. Because of the way our system is configured the console positions are incapable of monitoring "direct" or "talkaround" and are thereby not affected by the interference.

Make sure the monitor function isn't turned on... If it's a W9 XTL5000 consolette, the monitor function is normally assigned to the 0 (zero) key, if I remember right. Reading the radio with the CPS should tell you which key it's assigned to.

515 wrote:Make sure the monitor function isn't turned on... If it's a W9 XTL5000 consolette, the monitor function is normally assigned to the 0 (zero) key, if I remember right. Reading the radio with the CPS should tell you which key it's assigned to.

I honestly never even thought to check that I hope thats all it is!!!!

I don't think the monitor button serves the same purpose in digital as it does in analog.

I would check in the ASTRO tab of the conventional personality tab, and see what the Rx unmute rule is.

If "Digital CSQ" is selected - then your going to have the exact problem you describe.

Use the Help feature to pull up the definitions of each option.

-Alex

alex wrote:I don't think the monitor button serves the same purpose in digital as it does in analog.

I would check in the ASTRO tab of the conventional personality tab, and see what the Rx unmute rule is.

If "Digital CSQ" is selected - then your going to have the exact problem you describe.

Use the Help feature to pull up the definitions of each option.

-Alex

I have the astro Rx unmute rule set to normal squelch.
I'm pretty sure that "monitor" does have an effect on astro as well, I'll have to check on Monday.

what NAC codes are you using?

TWL911 wrote: I'm pretty sure that "monitor" does have an effect on astro as well, I'll have to check on Monday.

In Astro, "Monitor" will un-mute audio for encrypted traffic even if there are no matching Key ID's loaded in the radio for that traffic.

Pj wrote:what NAC codes are you using?

Currently set at 517. I don't remember what the other agency is using, but its NOT 517, or 379 which is what I will be using, if indeed the radio I was testing with was on monitor.