UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > General Vintage Technology Discussions

Notices

General Vintage Technology Discussions For general discussions about vintage radio and other vintage electronics etc.

Reply
 
Thread Tools
Old 21st Aug 2019, 11:28 am   #1
stitch1
Heptode
 
stitch1's Avatar
 
Join Date: Jan 2008
Location: Durham, County Durham, UK.
Posts: 549
Default The Cold War spy technology which we all use - Theremin

I've not come accross this intersting story before, maybe I'm not the only one so thought I'd share it.

https://www.bbc.co.uk/news/business-48859331#

John
__________________
www.valveradios.com
stitch1 is offline   Reply With Quote
Old 21st Aug 2019, 11:53 am   #2
g4wim_tim
Tetrode
 
Join Date: Nov 2018
Location: Freckleton, Lancashire, UK.
Posts: 90
Default Re: The Cold War spy technology which we all use - Theremin

I read that article with interest.

It worked on about 1GHz and used a cavity resonator with an audio diaphram as one side of the cavity, audio would phase modulate the reflected signal and be demodulated with what was effectively a direct conversion rx.

I experimented with and worked on a very similar system.

These days any high power illumination signal instantly raises attention from counter espionage types - plus you can determine exactly where the illuminating signal is coming from.

Mods - please delete this if not considered appropriate.
__________________
Building and tinkering for over 50 years, from 807's to digital amateur TV.
g4wim_tim is offline   Reply With Quote
Old 21st Aug 2019, 1:44 pm   #3
G8HQP Dave
Dekatron
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,807
Default Re: The Cold War spy technology which we all use - Theremin

I knew about that object, but I didn't know it was designed by Theremin.
G8HQP Dave is offline   Reply With Quote
Old 21st Aug 2019, 4:05 pm   #4
Refugee
Dekatron
 
Refugee's Avatar
 
Join Date: Apr 2012
Location: Worksop, Nottinghamshire, UK.
Posts: 4,175
Default Re: The Cold War spy technology which we all use - Theremin

I have seen a photo of it some years ago. It looked pretty simple inside.
Refugee is offline   Reply With Quote
Old 21st Aug 2019, 5:12 pm   #5
terrykc
Heptode
 
terrykc's Avatar
 
Join Date: Nov 2010
Location: North Hykeham, Lincolnshire, UK.
Posts: 502
Default Re: The Cold War spy technology which we all use - Theremin

I remember reading about that bug in the seal - presumably in 1960 but didn't realise how old it was. If it only took seven years before it was found and was presented in 1945, presumably it was discovered on 1952.

So why didn't we hear about it for another 8 years? Is it possible that, having discovered what was inside it, they used it to plant false information and didn't tell anybody about it until the USSR finally realised that they had been tricked.
__________________
Terry
When all else fails, read the instructions.
terrykc is offline   Reply With Quote
Old 21st Aug 2019, 5:22 pm   #6
turretslug
Nonode
 
Join Date: Nov 2011
Location: Surrey, UK.
Posts: 2,794
Default Re: The Cold War spy technology which we all use - Theremin

I'd heard of similar chicanery involving IR lasers being reflected off the windows of embassies and similar premises. Don't doubt for a moment that every possible (and some impossible!) means of finding out what the other side is saying has been thoroughly and expensively investigated and much of it won't escape into the public domain for decades.
turretslug is offline   Reply With Quote
Old 21st Aug 2019, 6:07 pm   #7
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 8,127
Default Re: The Cold War spy technology which we all use - Theremin

"The Conversation"...

Gene Hackman.

Lawrence.
ms660 is offline   Reply With Quote
Old 21st Aug 2019, 6:08 pm   #8
g4wim_tim
Tetrode
 
Join Date: Nov 2018
Location: Freckleton, Lancashire, UK.
Posts: 90
Default Re: The Cold War spy technology which we all use - Theremin

lasers off windows doesn't work too well far too much external noise - much better to focus on something inside the room, but net curtains are pretty good as a counter measure - or so I'm told ;-)
__________________
Building and tinkering for over 50 years, from 807's to digital amateur TV.
g4wim_tim is offline   Reply With Quote
Old 21st Aug 2019, 6:18 pm   #9
Andrewausfa
Heptode
 
Andrewausfa's Avatar
 
Join Date: Dec 2010
Location: St Ives, Cambridgeshire, UK.
Posts: 985
Default Re: The Cold War spy technology which we all use - Theremin

I bought a really interesting book about the subject a few months ago, essentially a history of the CIA's Office of Technical Services, 'Spycraft' by Melton, Schlesinger and Wallace. It goes into some detail (but not too technical unfortunately for us) about the items used during the cold war and how they were inserted into walls, rats, tables etc etc. The transition from valves to transistors was the big game changer evidently. I really recommend it.

Andrew

https://www.amazon.co.uk/Spycraft-H-...=UTF8&qid=&sr=
__________________
Invisible airwaves crackle with life. Or they should do.
BVWS Member
Andrewausfa is offline   Reply With Quote
Old 21st Aug 2019, 6:33 pm   #10
rambo1152
Octode
 
rambo1152's Avatar
 
Join Date: May 2010
Location: Manchester, UK.
Posts: 1,387
Default Re: The Cold War spy technology which we all use - Theremin

Quote:
Originally Posted by turretslug View Post
I'd heard of similar chicanery involving IR lasers being reflected off the windows of embassies and similar premises. Don't doubt for a moment that every possible (and some impossible!) means of finding out what the other side is saying has been thoroughly and expensively investigated and much of it won't escape into the public domain for decades.

In essence, that was the main story-line of a "The Avengers" episode called "All Done with Mirrors" that was first shown in 1968.

At the time me and my friend across the road had a modulated-light-beam telephone operating between our houses. Inspired by the episode, I noticed that each evening the sun reflected from the louvered glass windows in the shopfront of a nearby launderette into my bedroom so I turned my device towards it to see if I could hear the voices of those inside. There was plenty of noise from the vibration of the machinery, but that's all.

As for the American embassy incident, I was aware of it, but I had no idea that Theremin was involved. I suppose it's logical that detail like that wasn't available till after the fall of the Soviet Union.
One thing the BBC article doesn't mention and was alleged in the reports that I read, is that the the staff at the embassy suffered adverse health effects from the powerful non-ionising radiation beamed towards them.

Theremin died in 1993 according to his wiki entry, and according to the same source he devised the principle of raster interlace for television, I imagine like most television developments, there will be other contenders.
__________________
--
Graham.
G3ZVT
rambo1152 is offline   Reply With Quote
Old 22nd Aug 2019, 5:50 pm   #11
Brigham
Heptode
 
Join Date: Mar 2006
Location: Co. Durham, UK.
Posts: 829
Default Re: The Cold War spy technology which we all use - Theremin

Sanabria was using an interlaced raster from 1929, on the Western Electric television system. I wonder if Theremin was earlier than that?
Brigham is offline   Reply With Quote
Old 25th Aug 2019, 11:27 pm   #12
jamesperrett
Octode
 
Join Date: May 2007
Location: Alresford, Mid Hampshire, UK.
Posts: 1,001
Default Re: The Cold War spy technology which we all use - Theremin

Quote:
Originally Posted by turretslug View Post
I'd heard of similar chicanery involving IR lasers being reflected off the windows of embassies and similar premises.
I know that in the 80's we were interested in using lasers to measure water waves. The people trying to sell use the system claimed that it had been used to eavesdrop in the Iranian Embassy seige - the one problem they had was that they didn't want anyone inside to see the spot on the glass and so they had to try and attach a what looked like pigeon droppings to the window for something to aim the laser at.
jamesperrett is offline   Reply With Quote
Old 26th Aug 2019, 6:44 am   #13
G3VKM_Roger
Heptode
 
G3VKM_Roger's Avatar
 
Join Date: Jun 2012
Location: Southeast Norfolk, UK.
Posts: 514
Default Re: The Cold War spy technology which we all use - Theremin

I have a service manual for the 1929 Theremin musical instrument, quite a simple device. The most famous use of it was for the eerie soundtrack to "Forbidden Planet" in the late 1940s.

Cheers

Roger
G3VKM_Roger is offline   Reply With Quote
Reply

Thread Tools



All times are GMT +1. The time now is 5:22 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Copyright ©2002 - 2019, Paul Stenning.