Type II Simulcast Distortion

[KevinC]

Lol. I get severe static and complete drop outs (no control channel) (no signal) on an sds200 while monitoring a smartzone system (analog) at times.

Not much you can do on the subscriber side to clean up analog simulcast.

 

[dave3825]

I always just dealt with it. Thankfully the system will be gone at some point as the P25 side sounds pretty good.

 

[wtp]

i have described simulcast problems as,
a human can hear and make out voice with a little echo or phase shift.
so a 'yes' can sound like 'yyeess' and you can make it out.
but to a computer 11001010 means one thing but with a little echo 1l1l0o0o1l0o1l0o means nothing, so the radio goes silent.

 

[MTS2000des]

Our old analog simulcast Smartnet system was one of the first in the country. Towards the end of it's life, monthly mod comps were a must. Even then, multipath static was a reality of life, especially if one was at the edge of the footprint with sites equidistant. While I miss the "sound" of our old system, down to the Astro Tac comparator with the de-key "click" and being able to know which RFSS someone was being voted on just by the audio characteristics, I don't miss the drifting VCOs and internal thermal noise of those old MSF5000s.

It was only more noticeable on scanners. 1990 called and wanted the MTC3600 and Ball Efratom rubidium clocks that lost their minds back.

 

[gtaman]

Is this what you were referring to?

If this is what subscriber radio sound like, I can't understand how they think this is acceptable.

The video sounds like my eXRS radios 🤣

Yes subscriber radios sounded the same.

 

[wa8pyr]

Yes subscriber radios sounded the same.

Lord, 10 years ago. I heard at least two people I know in that recording.....

 

[gtaman]

Lord, 10 years ago. I heard at least two people I know in that recording.....

MTS2000s were the radio of choice during that time.

Sometimes I wish we could go back in time for a day.

 

[CanesFan95]

Yeah, those analog systems were always scratchy. It was aggrivating how you could have a high signal srtength and get a scratchy carrier. And if you happen to hear a real police radio somewhere, those would sound just as bad as a scanner. VHF / UHF signals go further and don't need as much (if any) simulcasting to cover a large area. I've never been a fan of 800 MHz.

 

[wa8pyr]

Yeah, those analog systems were always scratchy. It was aggrivating how you could have a high signal srtength and get a scratchy carrier. And if you happen to hear a real police radio somewhere, those would sound just as bad as a scanner. VHF / UHF signals go further and don't need as much (if any) simulcasting to cover a large area. I've never been a fan of 800 MHz.

They weren't scratchy around here, at least not until the PM started getting deferred as we moved toward P25.