Poor man's "bug detector"

[poltergeisty]

So I bought this basic "bug detector" on eBay. Here it is: https://www.ebay.com/itm/G318-Anti-...h=item1eeaedc6ac:g:mZoAAOSwzqxbpZX3:rk:4:pf:0

I know it's overlay priced and won't detect the professional stuff, not by a long shot, but being the gadget/Tech dork I am I had to buy one and test it. Surprisingly enough it does go off with my DECT 6.0 phone, albeit I don't know if that's due to something else, but I can tell you as soon as I fetch caller ID on the handheld and the signal interrogates the base station, the detector goes off. It also did detect my smartphone as I made a call. It doesn't detect WIFI unless you place the antenna close and then the light meter pulsates.

So question: How was this able to detect DECT 6.0 and GSM? I thought those modulation schemes would be out of the hands of a normal near-field detector like this?

 

[scanmanmi]

It just detects EMF radiation. Put it next to your microwave, house smart meter, walkie talkie, maybe even your refrigerator. Keep us updated on how it performs.

 

[poltergeisty]

It's not EMF radiation, I tested that. I do have an EMF meter, too.

 

[krokus]

My guess, is a few tuned circuits pick up RF, rectify it, and that triggers the alert circuit.

Sent using Tapatalk

 

[jwt873]

Says right on the device "RF Detector". It doesn't care about what modulation scheme is being used.

That's all it is.. A very wide band receiver (shows 1MHz-8000MHz in the specs) As krokus points out it sounds an alarm and shows the relative strength on the display.

 

[poltergeisty]

Okay, thanks.

 

[lmrtek]

It's a rf field strength meter and its all you need to track down any rf device

 

[vagrant]

It's a rf field strength meter and its all you need to track down any rf device

+ time...plenty of time