Usually, a meter is mounted in a metal case - to provide screening. That one is in an 'anti' metal case - so presumably this item is deliberately designed so that the case does not disturb the circuit within it: that carries connotations of high-frequency tuned circuits. I also see what looks like two very low inductance coils, which, in turn suggests a VHF transformer. The primary can be seen to be connected to the single wire and the socket, thereby possibly providing a pick-up loop for collecting EM energy from a radiated field. Then by transformer action, the resultant voltage is coupled into the transformer secondary and then connected to the two diodes - which can be clearly seen. The FSD of the meter, 2 mA, is suggestive of the item's application, too
So, put all that together: I reckon it's a field strength meter - probably for VHF use.
Al. / Nov. 03, '13 //
So, put all that together: I reckon it's a field strength meter - probably for VHF use.
Al. / Nov. 03, '13 //
