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Author Topic: 6761 kHz USB Radio Checks Presumably USAF 2139 UTC 7 Nov 2018  (Read 153 times)

Offline R4002

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6761 kHz USB 6.761 MHz USB presumed USAF HF SSB traffic English language sounded like military comms

Heard three short beeps and then some "check check" and other radio check sounding traffic...this is apparently one of the old USAF SAC frequencies. 

Very weak pescadore/freebander QRM down in the noise...

Heard via Westminster, MD SDR
U.S. East Coast, various HF/VHF/UHF radios/scanners/receivers - VHF LMR network operator

Offline autovon

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Re: 6761 kHz USB Radio Checks Presumably USAF 2139 UTC 7 Nov 2018
« Reply #1 on: November 07, 2018, 2217 UTC »
You are correct, 6761 was an old SAC freq, but used these days as kind of a tanker common HF frequency.  I have seen some tanker command posts also use it, or within 10-20 khz of there.

Offline R4002

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Re: 6761 kHz USB Radio Checks Presumably USAF 2139 UTC 7 Nov 2018
« Reply #2 on: November 08, 2018, 1300 UTC »
Nice, autovon.  I tuned in at the tail end of the comms on frequency so I wasn't able to hear any callsigns or other form of IDs.  Maybe somebody was doing a radio check and then switching to another frequency or band because I didn't hear anything else after the radio checks completed.
U.S. East Coast, various HF/VHF/UHF radios/scanners/receivers - VHF LMR network operator

Offline Josh

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Re: 6761 kHz USB Radio Checks Presumably USAF 2139 UTC 7 Nov 2018
« Reply #3 on: November 08, 2018, 1824 UTC »
Back in the day (Late 80s early 90s) all the cool kids tuned to 6761 upper. You could expect everything and anything to pop up here, even tho it wasn't an official Giant Talk qrg it was used as an intercom much like 123.45 is used by civil pilots. Whenever you're on one of these flyboy freqs and you hear a short growling sound and maybe a pip, stick around, someone just autotuned their hf rig in their aircraft to that freq and are about to make a transmission. You'll hear this all the time on triple one.

I thought 6761 was in the ZULU pool but it's not according to the last grq list I have;
Z100 3068.0
Z105 3116.0
Z110 3134.0 (tentative)
Z115 3143.0
Z120 3295.0
Z124 Unknown
Z125 4495.0
Z130 4472.0
Z135 4745.0
Z140 5026.0
Z145 5705.0
Z150 5800.0
Z155 5875.0
Z160 6715.0
Z165 6757.0
Z170 7831.0
Z174 Unknown
Z175 9016.0
Z180 9057.0
Z185 9809.0
Z190 10204.0
Z195 Unknown
Z200 11181.0
Z205 11494.0
Z210 11229.0
Z211 12070.0
Z215 13242.0
Z220 13245.0
Z225 13907.0
Z230 15046.0
Z235 15094.0
Z240 15097.0
Z245 Unknown
Z250 15962.0
Z255 17973.0
Z260 18006.0
Z265 18024.0
Z270 18027.0
Z275 18046.0 (tentative)
Z280 18387.0
Z285 Unknown
Z290 19665.0
Z295 19755.0
Z300 20167.0
Z305 20407.0
Z310 23337.0
Z315 23872.0
Z320 24828.0 (tentative)
Z325 24978.0 (tentative)
Z330 26532.0 (tentative)
Z335 26859.0
Z340 Unknown
Z345 Unknown
Z350 Unknown


I can't remember if it was on 6761 or 11175 (triple one) where I heard a pp between a USAF general officer in flight talking about closing our base in Panama before it ever hit the news, a comms officer broke in and told him the line was not secure, pissing off the general and ending the pp.

Good times.
« Last Edit: November 08, 2018, 1841 UTC by Josh »
Conveniently located near Vincennes Indiana.

Offline R4002

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Re: 6761 kHz USB Radio Checks Presumably USAF 2139 UTC 7 Nov 2018
« Reply #4 on: November 08, 2018, 2049 UTC »
I've heard some interesting things on 123.450 MHz, its almost like air-to-air CB, private pilots in Cessnas chatting away, airliners, etc. 

Nice frequency list by the way Josh.  I'd love to see one of the channel programming plans for these military aircraft HF radios.  I know a lot of the time they're just punching in a frequency but there's also heavy use of the preset channel function and alphanumeric IDs for frequencies (instead of reading the frequency over the air). 
U.S. East Coast, various HF/VHF/UHF radios/scanners/receivers - VHF LMR network operator

Offline autovon

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Re: 6761 kHz USB Radio Checks Presumably USAF 2139 UTC 7 Nov 2018
« Reply #5 on: November 09, 2018, 0017 UTC »
6761 active today with at least 3 different aircraft doing comm checks.  SNOOP, TOPCAT, HAPPY and another not IDd.

Offline Josh

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Re: 6761 kHz USB Radio Checks Presumably USAF 2139 UTC 7 Nov 2018
« Reply #6 on: November 09, 2018, 1932 UTC »
I've heard some interesting things on 123.450 MHz, its almost like air-to-air CB, private pilots in Cessnas chatting away, airliners, etc. 

Nice frequency list by the way Josh.  I'd love to see one of the channel programming plans for these military aircraft HF radios.  I know a lot of the time they're just punching in a frequency but there's also heavy use of the preset channel function and alphanumeric IDs for frequencies (instead of reading the frequency over the air).

I think there's some hf presets in this pdf;
http://www.carmachicago.com/profiles/Milair.pdf
Everyone interested in mil air should have this pdf, but some info is dated. Likewise, the zulu qrgs I listed are not used much anymore at all, however sometimes you do catch a flight saying meet me on zulu xx or we have such and such station on zulu xx.
If they still use the same qrgs, expect the zulu freqs to become active in ww3 with calls like WAR, NIGHTWATCH 01, etc.
« Last Edit: November 09, 2018, 1935 UTC by Josh »
Conveniently located near Vincennes Indiana.