RE: RF CT

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Thomas <tom-at-pwrcom-dot-com.au> 

 > Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com>
 >
 >
 > This process is detailed in my early book (1986) "Modern Resonance
 > Transformer Design Parameters".
 >
 > What size meter did you use?
 >
 > Dr. Resonance
 >

I used a small 100uA FSD moving coil (DC) edge meter, 1K75 coil resistance
and a 0-10 scale.

It's the one on the left in this photo:

http://international2.farnell-dot-com/info/catimages/PAN12.LR


I cant upload pics to my web space at the moment (firewall at work) so I'll
try my best to describe the circuit:

I used a 1" OD toroidal core I had lying around, no idea what the material
is, but its painted blue.

7 turns of 1mm diameter enamelled Cu wire wrapped around the core feeds two
BAT85 diodes.
  One to short the negative half of the cycle, and one to pass the positive
half to a 0.001uF smoothing capacitor.

This is then fed through about 4m of shielded twisted pair to a 10K pot (in
series with one of the wires and the wiper shorted to one side of the pot),
and on to the 100uA FSD meter.

I thought about full wave rectification but that would introduce twice the
diode voltage drop, and that becomes significant at the small currents I'm
trying to measure.

Tom L.