ENIGMA 2000 Newsletter - Issue 3

March 2001
Articles, newsreports and Items of interest : e2k_news@hotmail.com

Notes on jamming

E03 Lincolnshire poacher

Jamming of Lincolnshire Poacher transmissions appears to have ended around July of 2000 and at present no jamming is taking place. The end of jamming seems to have coincided with an improvement in diplomatic relations between Britain and Iran.

LP as doggedly continued against a barrage of jamming since at least the late 1980s. The only sign that things were getting too much was when the 10.00 and 11.00 UTC transmissions were dropped.

The pattern of jamming used to be operational between 10.00 and 14.45 UTC with a break until around 18.00 or 19.00 UTC, then resuming until 22.45 UTC, the reason for this break was probably due to the more pressing need of Iran to block incoming clandestine stations. Clearly it is a priority of those in power to stop the general populous hearing distasteful remarks about the regime, particularly so over that of some incomprehensible numbers and a rather quaint folk tune!

During the daytime all 3 frequencies were blocked, but often only two of the three frequencies would be jammed in the early evening and even then sometimes the wrong frequencies at that, this inconsistency was probably due to a lack of available jammers. It should of course be remembered that jamming can be switched on and off at the will of those in control. LP's complex sliding schedule is however very useful in ensuring that the message would get through.

E03a Cherry ripe

Although I have never noted jamming of Cherry Ripe some interesting points can be noted about how it operates, when it first started it followed the E03 format of operating on 3 frequencies and sending the call for 10 minutes. It is possible that the operators did anticipate jamming, perhaps from China or North Korea. Clearly relived that this did not materialise the station later dropped one frequency and reduced the call time to 7 minutes. On the subject of jamming from China they claim they do not block incoming foreign broadcasts (not), that hideous noise you hear mixed with radio Free Asia is usually a China Radio broadcast on the same frequency. This China does not class as jamming - it just happens to be there by chance (!) and allows them to claim they do not jam.

E05 Counting stations

During the late 1980s until the mid 1990s some E05 Counting Station transmissions were jammed, although I cannot confirm the source it was widely believed to be Iran or Iraq. The jamming was less blanketed than that used against E03, possibly monitors within the country involved would inform the jamming station of a transmission, and if facilities were available jamming would commence. These monitors also had to locate the second frequency, which they usually managed to do within the 10 minute preamble. They also used the method of switching off the jammer periodically to check if the station was still present and then resume jamming. The jammers never quite got to grips with the mysterious call '383' - this was unique in English language Counting Stations, (V05 had '545'), in that it sent a normal call 1234567890 - 383 etc, for the usual 10 minutes, no tones were sent and no message ever followed - it just ended. Jammers however continued to jam it until they realised it had gone! No jamming was ever noted of German or Spanish language Counting stations.

The jammers also turned their attentions to the 4F control transmissions, these always commenced on the h+30 and usually sent a small number of 4F groups repeated on a loop for 10 minutes. I certainly remember the 17.30 UTC transmissions been jammed.

Others

In my years of monitoring (since 1975) I have not noted other jamming against Number Stations, it is surprising the E10 stations have not attracted such attention, Israel as operated their network for many years. Both North and South Korea have jammed each others number transmissions, but, I can only assume that it was a 'gentleman's agreement' certainly between Western Europe, Eastern Europe and the Soviet Union not to deliberately interfere with each others intelligence transmissions.