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Author Topic: A temporary repeater on 151.625MHz, VHF DOT FREQ? It was...  (Read 459 times)

Offline ThaDood

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A temporary repeater on 151.625MHz, VHF DOT FREQ? It was...
« on: December 04, 2023, 2145 UTC »
Thursday afternoon, 11/30/2023, I was again hearing chatter on that VHF Licensed DOT Colored FREQ of 151.625MHz, over a scanner. Usually, it's the tower workers using that to communication when climbing that American Tower, 600ft TV tower, that's 1 mile North of me. However, I was hearing a +1 sec repeater tail on this, this time. A portable / mobile flat-pack repeater? Must have been, since I didn't hear that the next day. That, and I was getting ready for work Thursday afternoon. That, was different.
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Offline R4002

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Re: A temporary repeater on 151.625MHz, VHF DOT FREQ? It was...
« Reply #1 on: December 14, 2023, 1504 UTC »
Thursday afternoon, 11/30/2023, I was again hearing chatter on that VHF Licensed DOT Colored FREQ of 151.625MHz, over a scanner. Usually, it's the tower workers using that to communication when climbing that American Tower, 600ft TV tower, that's 1 mile North of me. However, I was hearing a +1 sec repeater tail on this, this time. A portable / mobile flat-pack repeater? Must have been, since I didn't hear that the next day. That, and I was getting ready for work Thursday afternoon. That, was different.

151.625 MHz is the RED DOT frequency, and its an itinerant frequency.  There are licensed users of this frequency with portable/temporary repeaters on their licenses.  Much like

451.800
451.8125

464.500
464.550

are mostly used for simplex comms, as are

456.800
456.8125

469.500
469.550

But temporary repeaters / portable repeaters operating on those frequencies (low side is repeater output, +5 MHz is the input) are also quite common.

With VHF, the itnerant frequencies are:

151.505
151.5125
151.625
151.640
151.700
151.760
154.5275
158.400
158.4075

With 151.625 MHz having the least restrictions on power output.  Usually the input will be 154.5275, 158.400 or 158.4075, but there's nothing stopping somebody from using, say, 151.505 or 151.5125 or 151.700 or 151.760 as an input frequency, as long as they are licensed appropriately. 

Around here, there are plenty of low power (handheld) users of 151.625 and the others, along with a handful of high power (110+ watts) licensed itinerant users.  One of the Medevac helicopter providers for this area has a backup system that uses 151.625, 152.5275 and 158.4075 (with DCS coded squelch).  I've heard their dispatch traffic over those three frequencies, when, for whatever reason, they are having difficulty with their main dispatch system on UHF.  I can't imagine the amount of QRM the aircraft have to deal with, especially on 151.625 MHz.
U.S. East Coast, various HF/VHF/UHF radios/transceivers/scanners/receivers - land mobile system operator - focus on VHF/UHF and 11m

 

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