The spy with no name
bbc.com
bbc.com
http://priyom.org/number-stations
E.g. number station on 6000Khz and IF 465KHz so local oscillator 6465KHz?
What happened when receivers went over to up-conversion and frequency synthesis?
They didn't actually placed tapping devices in the Queen's furniture. From the article:
One of his first ideas was to try planting listening devices in the Queen's furniture, he recalls, though he and his bosses realised it was technically unrealistic.
(At least that's what I thought when reading it anyway.)
A hotel waiter or a concierge is in the perfect position to mingle with the rich and powerful.
Upper class people use hotels for extra-marital affairs and business trips in unknown cities. You do not need a first degree connection with the military to get an in.
The bar of a famous Dutch hotel was known to be frequented by American spies and drug agents looking to ensnare peons of the local drug maffia, working their way up from there.
Moreover, this was about establishing a long term cover. He progressed through his cover career until he became an art dealer where he most definitely would have been hob nobbing with powerful people. Even if he didn't have access to "secrets" per se, he would have had access to useful information that would otherwise be hard to obtain.
The spy was probably burned from the beginning; an informant could have warned the Britsh(?) of his coming deployment and they in turn set the 'mother' on him.