Kai,
As an aside on the Y service stations, these were usually manned by impressed radio Hams who had a special permit to keep their own equipment. All other hams had their sets confiscated on outbreak of war.The stations themselves were administered by MI6 (I think).
Basically, the Y service stations operated in underground metal tanks (like petrol station tanks), to minimise interference from external sources as much as possible. Above ground, there would be an aerial tower and at least one hut for the relief operator, and cooking/sleeping etc.
The equipment ran on battery power, due to most of these stations being built in the back of beyond! Operators were required to listen to a predetermined set of frequencies for a set period every day, and stations were usually grouped in threes in order to get a triangulation on interesting signals.This was achieved using a piece of equipment called a Goniometer, which was basically two metal loops connected to air spaced capacitors for tuning. When the dial was turned, the loops moved in opposite directions and nulled out interference to allow the desired signal to be pinpointed.
About 15 years ago, there was an article in Shortwave Magazine about a farmer in England who decided to get rid of the underground obstruction which had interfered with ploughing on his land for decades.
He hired a JCB and started digging.....and eventually he found this big metal tank which turned out to be a lost Y station. No-one even knew it was there.
Regards,
Gordon GM0RMT
[ 06. March 2004, 01:16 PM: Message edited by: The_Historian ]
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