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Report #092 09/01/13

I ran across a strange signal on 13228.5 kHz. It was very raspy in the AM and CW receiver modes. Sent very slowly and did fresemble Morse code but it was uncopy. As I have done in the past, I sought the aid of an expert, Mike Chace-Ortiz, a Monitoring Times columnist. Mike identified the signal saying it was "A broken STANAG4285 transmission". Also appears on 11220 and 9007 kHz USB at night lately. Peaks to my SE which would place it in the southern Atlantic (a ship perhaps), SW Africa or somewhere like Ascension Island (more likely)." Many thanks to Mike for the details.

ShipCom is the United States only 24 hour provider of HF SSB radiotelephone and VHF radiotelephone Ship to Shore voice service. ShipCom stations, WLO Mobile AL, WCL Mobile AL, KLB Seattle WA and KNN Marina del Ray CA are all controlled from Mobile where operators are on duty 24 hours per day 7 days per week for radiotelephone Ship to Shore and Shore to Ship calls. Traffic lists and weather are available on the UTC hour. Gulf of Mexico, SW N Atlantic and Caribbean Sea at 0500 1100 1700 2300. East Pacific 0800 1500 2000. Alaska Offshore 0800 1500. For additional details go to http://www.shipcom.com/services.html

ENIGMA HM01 & M08a
The M08a messages are transmitted as cut numbers in CW. The HM01 transmissions consist of voice announced groups of 5F each followed by RDF. Barry Sanderson, KB9VAK, developed a multi channel, multiphase modulation known as Redundant Digital File Transfer. Barry also wrote the core software routines that allow RDFT to be used on personal computers using sound card DSP capabilities. The Cubans have adopted RDFT for transmission of some of the traffic to their Intelligence Agents at various locations. No doubt there is a list in the transmitter room indicating the schedules and corresponding frequencies. The transmitter operators likely do not know if there is upcoming traffic or not when they tune a transmitter. The message center probably passed the traffic via landline direct to the connected transmitter. Every now and then a transmitter will be tuned, but there is no traffic forthcoming and later the transmitter is shut down.

Over the years the Cubans have been notorious for sloppy commo operating procedures. Transmissions are often placed on the wrong frequency or on the wrong schedule or both. Sometimes when M08a messages are to be sent, HM01 traffic is put on the transmitter instead and that mode continues for some time before the error is recognized and corrected. During August I engaged in concentrated coverage of HM01 and M08a communications. I noted that as a sked nears completion the announced groups are repeated. I wondered if this was the tape starting over and the transmitter operator did not catch the mistake? Also the following sked frequently starts with the announced group after the last sent group of the previous sked. Sometimes they allow the transmission to continue and at other times they stop it promptly and start it at the first group. A number of times at the conclusion of a sked I have heard what sounded like a tape rewinding at high speed.

I still have a few skeds/frequencies to confirm and will then be able to prepare a master chart showing the complete activity.

14100 CS3B Madeira, Santo de Serra 261944
21150 OA4B Lima, Peru 261942
21150 OH2B Lohja, Finland 231607
24930 OA4B Lima, Peru 261930

  3484.5 OM/EE w/aero wx for Gander, Montreal, etc 260123
  4054 Spanish language religious bcst 2604134
10128.2 W0ER/B EM36 3WTS 031437. This is same as that hrd last month on 5064 at 191038.
13110 WLO, Mobile AL 271510
16121.8 Enciphered RTTY 45/854 271458
16375.5 2 OM (Asiatic) in conversation. 271451

End of Report

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