POR SATCOM 263.625MHz

[VK3RX]

Russian voice heard from 0612 UTC today on 263.625MHz

Clearly conversing with someone, but other station not heard. Went for quite some time.

This is a downlink frequency channel P17 so probably from UFO F4 or F8 @ 177.8W/171.8E.

 

[iMONITOR]

Other station Trump possibly?

What's required and involved with monitoring them

 

[zz0468]

Other station Trump possibly?

Awaiting instructions from his handler.

What's required and involved with monitoring them

A receiver capable of 225-400 MHz, AM and FM, 5 KHz steps. SSB capability is useful. Some sort of antenna, I actually get excellent results with just a discone. A 225-400 MHz passband filter, and a low noise preamp, better than 1 db NF. A scanner will hear stuff, but the synthesizer isn't usually quiet enough to do well unless signals are strong. And they CAN be. I use an R7000, Watkins Johnson 8617, and various SDR's. It's possible to see the idle passband noise of the satellite transponders with even a cheap SDR dongle if you have a decent antenna and preamp.

 

[VK3RX]

What's required and involved with monitoring them

Here you go - a bit of light reading:

UHF SATCOM Downlinks Receivable in North America

 

[iMONITOR]

Thanks guys for the info! I have a new AOR DV1 on the way, this sounds like fun! Regarding SSB, is it normally upper or lower sideband, or can it be either?

 

[RFI-EMI-GUY]

Russian voice heard from 0612 UTC today on 263.625MHz

Clearly conversing with someone, but other station not heard. Went for quite some time.

This is a downlink frequency channel P17 so probably from UFO F4 or F8 @ 177.8W/171.8E.

The Russians have an old terrestrial FM mobile phone system whose base station frequencies correspond with MILSATCOM uplinks frequencies. Usually you can hear some in band signalling dialing ringing and such in the beginning of the conversations. For some "odd" reason the US govt has never discouraged this interference. Likely it is being recorded in Langley.

Also, military air communications sometimes coincide with uplinks and those are in AM mode but are usually audible to an FM receiver.

 

[prcguy]

SSB for satcom or other? SSB on satcom has happened but its very rare and would usually be USB. Otherwise use FM for UHF satcom reception. On HF, commercial/military is always USB as is amateur above 10MHz. 160 through 40m amateur is LSB.

Thanks guys for the info! I have a new AOR DV1 on the way, this sounds like fun! Regarding SSB, is it normally upper or lower sideband, or can it be either?

 

[RFI-EMI-GUY]

I always found SSB (either upper or lower) mode helped find weak carriers when manually searching the SATCOM band . Of course, FM mode is needed to demodulate most of what is found.

 

[zz0468]

SSB for satcom or other? SSB on satcom has happened but its very rare and would usually be USB.

SSB with a narrow bandwidth will have a lower absolute threshold than any other voice mode. I use it to discern whether traces I might see are a local noise, or perhaps data in one of the narrow transponders. In SSB mode on the WJ and the R7K, I can get about an S5 just from passband noise. In FM, I can't even see it.

 

[db_gain]

The Russians know the uplink freqs to our birds so could potentially use them, they also have a few birds of their own with mil air band transpoders but seldom if ever use them. They've (bomber crews) been known to use the NATO ground to air qrf freq when visiting NATO countries with their Bear bombers. So everyone involved, Russian bombers, NATO intercept fighters, and ground control can all hear each other. The russkii milsat freqs were in some satelite book from ages ago, will have to look it up and post them.

 

[whitfieldjamesc]

Can I hear the ship?

 

[db_gain]

The Russians know the uplink freqs to our birds so could potentially use them, they also have a few birds of their own with mil air band transpoders but seldom if ever use them. They've (bomber crews) been known to use the NATO ground to air qrf freq when visiting NATO countries with their Bear bombers. So everyone involved, Russian bombers, NATO intercept fighters, and ground control can all hear each other. The russkii milsat freqs were in some satelite book from ages ago, will have to look it up and post them.

Russian Volna uhf sat up/down;
Up 335 - 399MHz
Down 240 - 328MHz

Dunno if volnas are still flying, perhaps the same bandplan is still in use on current birds. Russia isn't big on milsats for comms as they know the first to go in ww3 will be the birds. Also, why bother with the trouble of flying their own when they can use ours like everyone else?

 

[rcpcaetano]

Hello. I use this home antenna for satellite reception between 240 and 300 mhz. It is a 50cm satellite dish and in the middle of it I adapted an MMDS TV antenna part. Works great together with dongle sdr v3. hug to everyone.

 

[db_gain]

With regards to the above, apparently Russia has been using navsat/comsat birds for a long time now, with a store and forward and relay function for comms. In The Puzzle Palace (think it was in this book) there was detail of NSA efforts to force dump the stored load of a PAREUS sat over CONUS, it worked and they (allegedly) never did it again for fear the sat would tell Moscow on the NSA for hacking their bird over the US where they couldn't hear it.

So I imagine Russia still employs a store and forward as well as relay system in their sats, making them much more interesting to monitor.

"Soviet Parus (Sail) satellites comprised the top-secret Tsyklon-B network, which provided communications and navigation signals for the Soviet Navy. The constellation remained in service long after its declassifcation in Russia at the beginning of the 1990s and worked in parallel with the deployment of a new-generation GLONASS navigation network. The Tsyklon-B network was retired after the GLONASS constellation had become fully operational. A total of 96 Parus satellites were launched until 2010.
In addition to their navigation payloads, Parus satellite were believed to be capable of receiving, storing and re-transmitting communication messages by the Soviet military, first of all by the Navy."

Parus

History of Parus project by Anatoly Zak

www.russianspaceweb.com

Also see;

Parus (satellite) - Wikipedia

en.wikipedia.org

Russia's military spacecraft

Russia's military assets in space by Anatoly Zak

www.russianspaceweb.com

Tsiklon satellite

Tsiklon satellite

www.astronautix.com

 

[prcguy]

I don't see how this antenna could possibly work for UHF satcom reception. The disc elements from the MMDS antenna are tuned around 2162Mhz and the dish does basically nothing for those elements or any other antenna for the roughly 245 to 270MHz UHF satcom downlinks.

Hello. I use this home antenna for satellite reception between 240 and 300 mhz. It is a 50cm satellite dish and in the middle of it I adapted an MMDS TV antenna part. Works great together with dongle sdr v3. hug to everyone.

 

[Ubbe]

It is a 50cm satellite dish and in the middle of it I adapted an MMDS TV antenna part.

Looks like an offset dish and the focal point where all the signals are concentrated are at the end of that empty LNA boom. The tv antenna are set at another point in the center of the dish. Usually you can receive most of those sats with almost any kind of outside antenna. But as long as you receive what you want it is ok and serves its purpose.

/Ubbe

 

[rcpcaetano]

Here is the original antenna base. I only used her top

 

[prcguy]

That looks like a California Amplifier MMDS antenna/down converter. If so I've toured the assembly line for that unit in Camarillo, CA. It receives roughly 2.1 to 2.35GHz and the output to the TV set is 222 to 408MHz. Its antenna in no way will receive the 245 to 270MHz UHF satcom band. If it does at all then it would work on par with using something like a gas station filler nozzle as an antenna.

Here is the original antenna base. I only used her top

 

[rcpcaetano]

That looks like a California Amplifier MMDS antenna/down converter. If so I've toured the assembly line for that unit in Camarillo, CA. It receives roughly 2.1 to 2.35GHz and the output to the TV set is 222 to 408MHz. Its antenna in no way will receive the 245 to 270MHz UHF satcom band. If it does at all then it would work on par with using something like a gas station filler nozzle as an antenna.

Ok, I totally agree with you. But even though I know it's not an appropriate antenna, I use this antenna for reception of the 250 MHz band. It may not be the exact antenna, but it works a little. this is one of the videos I put on youtube with that antenna

 

[db_gain]

Holy cow that thing works great for whatever reason! From now on will check the output of any sat antenna for hidden gems!