P25 Pre-recorded voice

Squad10 · #1 (**permalink**) 07-22-2009, 02:30 PM

Heard what sounded to be a pre-recorded voice message on High Risk Metropolitan Area Interoperability 25 Cities Project (Chicago) frequencies today. Each pre-recorded message was repeated three times during a single keyup.

I'm thinking some type of alarm or alerting method.

Anybody else hear anything similar in your area?

theshadowman · #2 (**permalink**) 07-22-2009, 02:54 PM

What did the pre-recorded message say?

Squad10 · #3 (**permalink**) 07-22-2009, 03:23 PM

Quote:

Originally Posted by theshadowman

What did the pre-recorded message say?

Didn't record the transmission, but a male voice said something like "took the cross town bus", female voice said something about "the garbage is out", then something like "he's wearing brown shoes".

Josh · #4 (**permalink**) 07-22-2009, 03:49 PM

I believe those are test messages from a certain system analyzer/service monitor thing.

They may be tweaking the system.

Squad10 · #5 (**permalink**) 07-22-2009, 06:37 PM

Quote:

Originally Posted by Josh

I believe those are test messages from a certain system analyzer/service monitor thing.

They may be tweaking the system.

The system has been operational since mid 2007. Live communications tests (in the clear) are performed weekly between about 20 law enforcement agencies with perfect audio. I've never heard of such a test as you mention.

What makes you believe they are tests messages from a piece of hardware?

AlabamaRS · #6 (**permalink**) 07-22-2009, 06:51 PM

Any NACS??

N_Jay · #7 (**permalink**) 07-22-2009, 06:58 PM

Sounds like coverage or voice quallity tests.

Squad10 · #8 (**permalink**) 07-22-2009, 07:09 PM

Quote:

Originally Posted by AlabamaRS

Any NACS??

171.4375 and 168.9125 are the two freqs. I caught, both with NAC653(PSR500)

Squad10 · #9 (**permalink**) 07-22-2009, 07:10 PM

Quote:

Originally Posted by N_Jay

Sounds like coverage or voice quallity tests.

Sounded more like a VARDA concept to me.

diskmonger · #10 (**permalink**) 07-22-2009, 08:04 PM

I've heard the exact same messages on several Federal repeaters in the Detroit area. I know for a fact they are just tweaking the audio on the repeaters.

The phrases you heard contain certain syllables and sounds that are used in the calibrations.

N_Jay · #11 (**permalink**) 07-22-2009, 08:06 PM

Quote:

Originally Posted by Squad10

Sounded more like a VARDA concept to me.

Really?

With those phrases?

Squad10 · #12 (**permalink**) 07-22-2009, 08:52 PM

Quote:

Originally Posted by N_Jay

Really?

With those phrases?

Any voice phrase can be recorded by a VARDA unit. I've recorded MDC signalling and DTMF using a VARDA, the selective signalling was always decoded properly.

Squad10 · #13 (**permalink**) 07-22-2009, 08:53 PM

Quote:

Originally Posted by diskmonger

I've heard the exact same messages on several Federal repeaters in the Detroit area. I know for a fact they are just tweaking the audio on the repeaters.

The phrases you heard contain certain syllables and sounds that are used in the calibrations.

Thanks diskmonger, your reply was one I was hoping to get.

N_Jay · #14 (**permalink**) 07-22-2009, 08:54 PM

Quote:

Originally Posted by Squad10

Any voice phrase can be recorded by a VARDA unit. I've recorded MDC signalling and DTMF using a VARDA, the selective signalling was always decoded properly.

Sure, but what would be the purpose?

Unless you think these are code phrases?

Seems like a stretch compared to thinking they are recorded phrases for audio quality testing.

But maybe?