Re: [TCML] HV Panel Meters

[Ed Phillips <evp@xxxxxxxxxxx>]

How about a thermocouple type ammeter? Like the ones used to measure RF  
antenna current. Aren't they true RMS reading too?

Tony Greer"

	Yes and I've used them in this application.  [For ammeters, that is.]  Problem is cost and easy burnout so you have to be very very careful you know what you're doing.  Light bulb technique works very well and is a lot easier than finding meters. Of course, you have to pick a bulb whose resistance is small compared to the circuit resistance and which will give significant light at the desired current.  At one time Sylvania made a series of tubes with two filaments mounted side by side.  RF current to be measured could be fed through one and DC current through the other.  By matching the brightness by eyeball [quite sensitive] and measuring the input to the the reference one quite accurate measurements were possible.

Ed


_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla