169.575 131.8 PL Tone - Fire Dispatch - South Central Texas

Folks,

I've recently copied a public safety fire/ems dispatch on 169.575 with a PL of 131.8 - very faintly though here to my location in San Antonio. Heard a reference to "Hwy 37" in the dispatch.

I've confirmed that it isn't an image (used two different radios with different IFs) - could it be some kind of point to point link?

Any ideas?

It might be a vehicular repeater. Somebody was using those on several frequencies in the federal band in the Mineral Wells area several years ago. The ones I heard were the simplex in-band type that drop the carrier about once a second. It happens so fast it sounds like ticking instead of dropping out like you get with priority sampling on a scanner. Did you hear anything like that?

I would not be surprised if it has something to do with Atascosa County. For many years, persons unknown operated a 'range extender' which used--of all frequencies-- 154.600 NO PL as the input, with the output being Atascosa Co Fire (153.95) There were times that for hours, gravel haulers, construction workers and other seemingly legitimate itinerant users were unknowingly having their traffic rebroadcast on a public safety frequency. One time, a friend and former Fire Chief was coming back to Bexar County from a fishing trip and I heard their convoy's car to car conversation for at least a half hour before they got home.

There was a 131.8 Report in Dallas area, turned out to be the VA using it for Parking Lot Call Boxes

nd5y said:

It might be a vehicular repeater. Somebody was using those on several frequencies in the federal band in the Mineral Wells area several years ago. The ones I heard were the simplex in-band type that drop the carrier about once a second. It happens so fast it sounds like ticking instead of dropping out like you get with priority sampling on a scanner. Did you hear anything like that?

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scrotumola said:

I would not be surprised if it has something to do with Atascosa County. For many years, persons unknown operated a 'range extender' which used--of all frequencies-- 154.600 NO PL as the input, with the output being Atascosa Co Fire (153.95) There were times that for hours, gravel haulers, construction workers and other seemingly legitimate itinerant users were unknowingly having their traffic rebroadcast on a public safety frequency. One time, a friend and former Fire Chief was coming back to Bexar County from a fishing trip and I heard their convoy's car to car conversation for at least a half hour before they got home.

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When I get a chance I'll monitor Atascosa County's Fire Dispatch to see if it is a rebroadcast... it is definitely a repeater on 169.575.

There are a few legacy (or still active?) allocations for public safety in the 162-174 MHz range... but this one is new to me.

Then again, SAMC has a paging repeater that blasts HUGE amounts of RF all over the 162-174 MHz band which is out of control. It's frequency is 167.86250 - but my goodness it blasts out sub-carriers all over the VHF band. I cannot believe the FCC / NTIA hasn't gotten involved. It's almost as if the contractor on the project just decided to use max power and no filtering

blantonl said:

I've recently copied a public safety fire/ems dispatch on 169.575 with a PL of 131.8

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I started hearing this last July but I locked the frequency out thinking it was an image or intermod. I unlocked it today on my scanner located on the south side of San Antonio, I'll post up if I hear anything.

scrotumola said:

I would not be surprised if it has something to do with Atascosa County.

Click to expand...

Good guess! Heard an EMS dispatch for Jourdanton EMS at 4:35 this afternoon.

Audio file: https://sites.google.com/site/okiesam/Home/vhf-high/169-5750

Here is something hilarious - it appears that CBP recently stood up a repeater on 169.575 here in the San Antonio area, in addition to a repeater that seems to be further south.

NAC A80 is local to San Antonio
NAC 301 is remote, probably down south of San Antoni

CBP in Texas is slowly switching to the new DNET frequencies popping up nationwide. This is probably one of the new ones. BP for me at least seems really quiet in SA