Tuesday, March 06, 2007

7000 kHz Is Getting Weird

For the last several days, there has been a real zoo on 7000 kHz, right at the lower end of the 40 meter band. Some people have heard a STANAG 4285 signal that decodes to the usual French Navy testing loops complete with Voyez le brick and identification as FUV (French Navy, Djibouti). Parameters are 300/L/5N2/ITA2.

It may or may not be coincidental that Djibouti and the African "horn" in general is a world trouble spot you don't hear much about, with several important oil fields, tanker routes, and natural gas pipelines at stake. Military activity is greatly increasing there as of late.

Other signals being heard are hours of conversation in Spanish, using procedures such as "Cambio" for "Over." There is a little of the whistling which seems to be a test tone down there, and a little of the hooty sounding multiband inversion scrambling used by the Mexican Army and/or ???.

Finally there are at least two ALE signals, one from the Italian Carabinieri phone patch net which passes an AMD string of "DIAL4," another with short alphanumeric IDs which are still unknown.

This is not counting a weird artifact that has been transmitting on a wide range of 40 meter frequencies for years, producing a short beep every minute or so. It is a weird dual-frequency beep resembling a DTMF tone but not one. I suspect it's local to Southern California.

It is not known whether any of this is legal on 40 meters. I personally suspect it is not, but it's a grey area. However, hams who tune up or send CW on 7000.000 in an effort to drive all this stuff off must have a lot of faith in their VFO calibration.