Tin-foil hats?

If that were true, then the stupidity of the secret service would be enormous. You can detect directed beams with almost anything, if they are strong enough to harm people. Hook a few diodes and wires to any sound system, and you start hearing things. Any fluorescent light tube would start emitting light, long before the beams became dangerous. Any engineer can think of a host of gadgets to detect those beams. So, either the sec.serv. guys are stupid, or there were no secret beams.

The non-specific symptoms sound more like conversion disorder, or when people on antidepressant/sleeping medication long-term come off their meds too fast. Were they giving them all happy-pills? Probably...

We used unconnected LEDs to find leaks from waveguide junctions on a 1 MW radar.

But, if it were a matter of a few episodes, it's unlikely the diplomats would 'detect directed beams' when outside the embassy. The whole point of beams is that they can be aimed, and the operators can hit-and-run.

Snipers can be very elusive, even though their shots are visible and detectable, because they can hide themselves.

Microwave radiation does make more sense than ultrasound, but... it always did. Evidence, though, is a hard problem: what traces would remain behind? Brain tissue damage?

Testing for "after effects" is rather useless. Giving your embassy people a small warning device the size of a pack of sigarets would be so much more useful. It would also cut down on attempts , if you carefully leaked the presence of such packs.......

I'd expect that an embassy or diplomatic residence would be saturated with RF and laser detectors.

This kind of stuff goes way back to "The Thing" at the Moscow embassy: Oddly, the Havana version uses pulsed RF instead of CW. At microwave frequencies, almost any moveable metal diaphragm will produce FM modulation and can be used as a listening device.

However, it's not easy. Besides picking up a very weak reflection, the building is full of other reflections, all of which interfere with the desired reflected signal. I other words, it doesn't work very well.

I only know about one embassy from about 45 years ago. All the windows were sputtered with aluminum for RF proofing and specifically to avoid RF bugs.

The Havana article is far too vague to be considered authoritative.

And the purpose of that would be... what? The US would send a new batch of diplomats, there are plenty.

Best regards, Piotr

Flashbulbs are more fun! Single use though...

Surveillance of talk by doppler backscatter off random objects (can be done with lidar, too). The embassy in Moscow had an embarassment of microwave radiation directed at it, long time ago...

On a sunny day (Mon, 7 Dec 2020 20:02:52 +0200) it happened Tauno Voipio wrote in :

I have one of these:

At about 5$ .. you can adjust the sensitivity. I usually calibrate it by holding it close to a raspberry pi1 (in a plastic housing) and setting it so it just goes of. With that setting you even get a beep when the neighbor across the road unlocks his car door. Any WiFi, cellphones close in the street, will trigger it, Holding it near your microwave also triggers the alarm.

I am sure the US security club has much better ones, and recording spectrum analyzers that can be left on 24/7. Long ago the Russians were beaming microwaves to the US embassy to charge or power ? their listening bugs... What we do not know is what frequency microwaves the OP was talking about, Above 5 GHz you need a better detector than the 5$ ebay one.

Anyways we live in an age where 'China or Russia has done' it US media.

How quiet is CNN and other media now China did an automatic docking in moon orbit for a sample return. I found some nice pictures on the Chinese website:

I wanna be in 'Merrica ???? Some may remember Westside Story, I have the DVD. OK back to tronics... A 3 cent BAT diode and old fashioned 100 uA moving coil meter should work too for high power, have that too.

Oh, sure, but then microwave irradiation is nothing more than an occupational hazard. Running a Diesel engine can cause cancer too, and we accept that fact. Truckers are expendable, and so are diplomats.

Best regards, Piotr

I have something similar. The problem is that it doesn't show anything about the transmitter except that something is transmitting on some frequency. Instead, I prefer to use an RTL-SDR dongle and some spectrum analyzer software.

Nope. They were using the RF reflected from a moving diaphragm and listening to the reflection for FM modulated voices: The amount of RF field strength needed to hear useful reflected signals from such a tiny diaphragm must have been huge. I could probably cook my dinner on the RF needed. Detecting it should have been trivial with any kind of ELINT hardware.

Groan. I was a juvenile delinquent when the movie appeared. Like in the movie, all us kids formed gangs. What do gangs do? Beat up on each other, like in the movie. I ended up on the receiving end of a steel pipe across the back of my head. I survived, but now hate the movie and the music.

Yeah. That's called a FSM (field strength meter) or "sniffer". Also useful as a ghost detector. Very little sensitivity, but does work better if you add a tuned circuit to reduce pickup on undesired frequencies. 50 ua meters are more common than 100 ua.