three component RF detector

[peterlowrie]

I've been searching through the posts herein for a circuit.

The circuit I'm looking for is a wideband RF detector that uses just three components; an LED, a variable potentiometer and a coil.

The diagram would be the model of simplicity, the value of the VR and the number of windings and gauge of the copper wire coil would be key.

Anyone seen something like it. Suggestions?

Let's put it this way: When trying to find a transmitter (say a bug), what point using complicated circuits when most, although wideband,  are not wide enough to cover all bands. Once I saw this circuit in operation, it detected everything from a small AM and a smaller FM transmitter as well it detected into the gHz range - with three components!. Methinks the KISS principle raises it's beautiful head once again.

Regards
Peter Lowrie

[Hero999]

Do you want it to be self powered?

Here's the simplest solution:
http://www.electronics-lab.com/forum/index.php?topic=19564.msg89905#msg89905

It's not very sensitive and will only work if you're really close to a transmitter.