HFU HF Underground

Loggings => Utility => Topic started by: AlanC on June 10, 2017, 1532 UTC

Title: 11175 very busy
Post by: AlanC on June 10, 2017, 1532 UTC

11175 seems very busy again today, with DYNATRON sending many messages to ALL STATIONS prefixed FOUR-POSTURE and FOUR-RAZORBLADE.

Title: Re: 11175 very busy
Post by: Josh on June 10, 2017, 1747 UTC

I think that would be "FOR POSTURE" and "FOR RAZORBLADE".
As in the following transmission is for group or station callsign POSTURE and RAZORBLADE.

Title: Re: 11175 very busy
Post by: Looking-Glass on June 15, 2017, 0829 UTC

What mode?  SSB or CW or data?  Have heard nothing on 11.175MHz SSB over this way so far. ???

Title: Re: 11175 very busy
Post by: Josh on June 15, 2017, 1318 UTC

USB, it's a hfgcs channel, day primary.
https://en.wikipedia.org/wiki/High_Frequency_Global_Communications_System

Title: Re: 11175 very busy
Post by: MDK2 on June 15, 2017, 1321 UTC

Quote from: Looking-Glass on June 15, 2017, 0829 UTC

What mode?  SSB or CW or data?  Have heard nothing on 11.175MHz SSB over this way so far. ???

This is one of the US Air Force's HFGCS frequencies, which sends live transmissions of coded messages in NATO alphabet from several different US Air Force bases. All transmissions are voice and in USB. Other frequencies to check are 6739, 8992, 13200, and 15016. Transmissions may go out on all of them simultaneously, but the highest ones may be daylight hours only and the lowest one at night, North American time.

Title: Re: 11175 very busy
Post by: Unknown Name on June 15, 2017, 1613 UTC

1612 UTC rainan for id  "qcmggu standby qcmggumqcc2st3obh66m7oow57fpqt."

Title: Re: 11175 very busy
Post by: R4002 on June 15, 2017, 2040 UTC

When the HF-GCS system is as active as it has been, it makes an interesting propagation indicator.  Since they transmit on 4724 kHz USB, 6739 kHz USB (alternate 6MHz frequency: 6712 kHz USB), 8992 kHz USB, 11175 kHz USB (alternate 11MHz frequency: 11180 kHz USB), 13200 kHz USB and 15016 kHz USB...and since the transmissions are often simulcasted (and sometimes multicasted and simulcasted - that is, transmitted on multiple frequencies at once from multiple transmitter sites at once) you can often hear an echo on the "mid band" frequencies (usually 8992 USB and 11175 USB) due to multi-path propagation from several different transmitter sites.

On several instances I've heard different sites transmitting different messages on 11175, sometimes causing some pretty serious interference and QRM.

Next time you hear a lot of activity on 11175, take a look at (or a listen on, or both) 11180.  It, along with other nearby frequencies, are often used for datalink transmissions around the same time voice traffic is taking place on 11180.  You'll also find 11180 is often used for ALE sounding transmissions.

There are likely dozens of other frequencies that are part of the USAF HF-GCS system, including logged frequencies 6778 kHz USB, 6833 kHz USB, 6903 kHz USB, 6988 kHz USB and 7703 kHz USB.  Additionally, the COTHEN HF system (used by DEA, ICE, DHS, etc), the FEMA HF nets (SECURE, SHARES) and the Civil Air Patrol/CAP HF-SSB nets have had USAF and other US military traffic on them.  6765 kHz USB and 6845 kHz USB (both SHARES frequencies) can sometimes yield some interesting monitoring.


7615 kHz USB is the CAP (Civil Air Patrol) nationwide net primary frequency.  There are several 4MHz band regional net frequencies as well.
5211 kHz USB is FEMA-1 (FEMA HF night primary)
10493 kHz USB is FEMA-2
14597 kHz USB is FEMA-3 (FEMA HF day primary)
5236 kHz USB is SHARES night primary
14396.5 kHz USB is SHARES day primary
6910 kHz USB is SHARES Central
6765 kHz USB is SHARES North
6845 kHz USB is SHARES Northeast
7320 kHz USB is SHARES Southwest

It's a safe bet that most USAF, USCG, USN and USMC aircraft have the capability to communicate on the HF-GCS and COTHEN (Customs Over The Horizon Network) nets. 

Title: Re: 11175 very busy
Post by: Josh on June 16, 2017, 1427 UTC

"You'll also find 11180 is often used for ALE sounding transmissions."

11181



NIPR/SIPR HF ALE Network Frequency List

SIPR (Secure Internet Protocol Router) Network Frequencies
(USB/ALE): 3113.0 5702.0 5902.0 6715.0 8968.0 9044.0 11181.0 15091.0 17976.0 27870.0 kHz.

SIPR Gateway/Frequency Matrix/
ADWSPR Andrews AFB, Maryland 3113.0 5702.0 6715.0 8968.0 9044.0 11181.0 17976.0 27870.0

AEDSPR Elmendorf AFB, Alaska 6715.0 17976.0

CROSPR Croughton AB, United Kingdom 5702.0 5902.0 6715.0 8968.0 11181.0 15091.0 17976.0 27870.0

GUASPR Andersen AB, Guam 5702.0 8968.0 11181.0 15091.0

HAWSPR Ascension Island 5702.0 6715.0 8968.0 11181.0 15091.0 17976.0 27870.0

HIKSPR Hickam AFB, Hawaii 5702.0 5902.0 6715.0 8968.0 15091.0

ICZSPR Sigonella AB, Sicily, Italy 5702.0 6715.0 8968.0 11181.0 15091.0 17976.0

JDGSPR Diego Garcia, Indian Ocean 5702.0 6715.0 8968.0 9044.0 11181.0 27870.0

JNRSPR Salinas, Puerto Rico 3113.0 5902.0 6715.0 8968.0 11181.0 15091.0 17976.0

JTYSPR Yokota AB, Japan 15091.0

MCCSPR McClellan, California 5702.0 5902.0 6715.0 8968.0 11181.0

OFFSPR Offutt AFB, Nebraska 3113.0 5702.0 5902.0 6715.0 8968.0 11181.0 15091.0 17976.0

PLASPR Lajes AB, Azores 5702.0 6715.0 8968.0 11181.0 15091.0



NIPR (Non-Secure Internet Protocol Router) Network Frequencies
(USB/ALE): 3068.0 4745.0 5684.0 8965.0 10600.0 10830.0 11199.0 13242.0 17973.0 20631.0 kHz.

NIPR Gateway/Frequency Matrix
ADWNPR Andrews AFB, Maryland 3068.0 4745.0 5684.0 8965.0 11199.0 13242.0 17973.0 20631.0

CRONPR Croughton AB, United Kingdom 3068.0 4745.0 8965.0 17973.0

HIKNPR Hickam AFB, Hawaii 8965.0

ICZNPR Sigonella NS, Sicily, Italy 4745.0 5684.0 8965.0 13242.0 17973.0 20631.0

JNRNPR Salinas, Puerto Rico 8965.0

MCCNPR McClellan, California 4745.0 5684.0 8965.0 13242.0 17973.0

OFFNPR Offutt AFB, Nebraska 5684.0 8965.0 11199.0 13242.0 17973.0 20631.0