[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Level shifter problems

Original poster: "David Sharpe by way of Terry Fritz <twftesla-at-uswest-dot-net>" <sccr4us-at-erols-dot-com>


I'd start by checking your energy storage capacitors.  Check capacitance
and check resistance (if they have internal bleeder resistors).  It's not
a HV check I know, but will indicate if something major has happened
(like a shorted bleeder, cap with major C shift or shorted, etc.)

Check your diodes to make sure they are ok and blocking in reverse
direction.  A leaky or open diode could cause the UV condition you are

To check your MOT's, wire HV to HV and power one MOT with 120VAC
through a variac, a place a lamp or resistive load on 120V winding of
second transformer.  You should short duty be able to power up to 1kW
load without risking transformer(s).  This will tell if a winding or saturation
problem exists with either transformer...

Be careful checking this circuit out, and discharge capacitors after powering.
This circuit is DEADLY!!!

Dave Sharpe, TCBOR
Chesterfield, VA. USA

Tesla list wrote:

> Original poster: "J. B. Weazle McCreath by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <weazle-at-hurontel.on.ca>
> Hello Coilers,
> I've been working on putting together a new power supply and SRSG for my
> coil based on the MOT level shifter circuit that Henry Hallam has used.
> For some reason I can't get it to work.  I've checked all of the various
> individual components and all seems OK, but I get very low output voltage
> from the level shifter.
> The two MOTs are 2100 Volt units of identical manufacturer, as are the
> diodes and capacitors.  The protection circuit is as per Terry's site
> with a total of 1000 ohms in each leg.  The bypass caps are 500 pF. at
> 30 K.V. doorknobs.  I've checked and re-checked the wiring and can see
> no reason for it not working, but I'm only getting about 2 K.V. across
> the gap, which obviously isn't enough to fire it.
> Ideas anyone?
> 73, Weazle, VE3EAR/VE3WZL
> Listening: 147.030+ and 442.075+
> E-mail:    weazle-at-hurontel.on.ca
>            or ve3ear-at-rac.ca
> Web site:  www.hurontel.on.ca/~weazle