[Amps] Power factor and choke vs resonant-choke input supplies

Keith Dutson kdutson at sbcglobal.net
Fri May 11 12:10:00 EDT 2007

>I had a resonant choke in a full wave bridge rectifier supply using a pole
pig transformer. It was an attempt to use a pole pig with a pair of small
Eimac triodes. My intention was to come up with 3700 volts dc from a pole
I used the formula in Bill Orr's Handbook to determine values. My components
were VERY conservative. The filter capacitor was a power line power factor
correction capacitor, so it would handle many kV.

When I powered this thing up my 3-500Z's arced from anode to grid. Thinking
I had gassy tubes, I pulled the anode caps. 
When I powered up again a large bypass cap shattered. Then I clipped a HV
probe across the HV line, stood back a couple feet on a rubber matt, put one
hand in my pocket, and I turned on the toggle with the other. The television
CRT 2nd anode HV wire in the supply blew in two and it came out the open
door and attached to my wrist. I wound up with first through third degree
burns all up and down my arm. I had a charred hole the size of a quarter in
my wrist.


That is insane!  The pig poles I know about transform 7000 to 240 or
vice-versa, at enormous currents.  What size circuit (breaker size) did you
feed it with?

>Then I watched the second hand on a clock move and carefully noted I could
still think, hear, move, and see. I was frustrated I never paid attention to
how long a human could live with no heartbeat or with seriously flawed
After the second hand swept around and there was no change in my ability to
think, I assumed my heart was still running at enough capacity to get help,
so I made sure the power was off and I told my wife not to panic but we
needed to get some medical help.


You were old enough to be married when you did this?

73, Keith NM5G

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