Re: Recent s.s.t.c work

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "K. C. Herrick" <kchdlh@xxxxxxx>

Update:  I've added a few 5 V bypass capacitors & replaced a probe's 
ground-clip & now I find that I actually have negligible phase shift 
thru my 1:1 transformer and "pilot oscillator" circuit.  But I do see 
a significant shift thru the capacitor in series with the primary of 
the H-bridge's drive transformer.  It's currently only 3 uF so I will 
have to increase that quite a bit.

But I'm running out of room on the board.  I was amused by the 
proliferation of probes pursuant to this testing (an HP, a no-name 
and an ancient Tek) so I took a photo of it:
http://www.hot-streamer.com/temp/KCH_TCH6.jpg
The capacitor in question is the tubular one directly to the right of 
the probe with the red sleeve.

Those who recall a prior photo will note the surgery I've had to do 
on the board: adding a daughter board at the lower right to 
accomodate huskier transformer-drive transistors, adding another 
daughter board across the center to accomodate huskier plus-going 
gating transistors in the 4 IGBT-gate circuits, and sawing off a 
whole section of the board directly above the gate-transistor board 
so as to completely replace the rest of the  4 drive circuits.  I am 
too old for this.

If anyone's further interested, the blue/white tw-pair conducts the 
feedback from the 1:100 primary c.t. inside the bucket while the 
small gray tw-pair leads from the 4 m-ohm current shunt in the 
mains-capacitor bus to the scope.  The two diagonal white objects are 
just part of a lifting bridle.

KCH