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using SCR Re: 24 turns center tap neon primary.
you can use an SCR in an inverter circuit, but you must find a way to make
the current reverse - a typical way is to have a capacitor in series with
it - with SCR off, charge cap. Discharge into L, current will keep going
even with C dischaged (ILdv/dt), charging the cap to a reverse voltage, then
the current reverses turning off the SCR. Look in SCR manuals for other
more complex ways of doing this. More complex than a transistor circuit,
and also much more lossy at low voltages because of forward voltage drop -
you don't need HV hold off, you need super high current. Note that you can
remove the diodes from a car's alternator and have a handy source of 3 phase
AC - you can even tap into your alternator in front of the diodes and use it
for AC without installing a second alternator - JC whitney used to sell a
kit for doing just this
----- Original Message -----
From: Tesla List <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, March 29, 1999 2:48 AM
Subject: 24 turns center tap neon primary.
>Original Poster: gweaver <gweaver-at-earthlink-dot-net>
>
>I did some experementing today. I replaced a neon primary (241 turns of
>wire) with a new primary coil (24 turns with a center tap). I used #12
wire.
>I estimated 241 turns by counting the layers and number of turn on one
layer.
>
>I have a DC to AC converter that I built that uses an output transformer,
>10:1 ratio step up from 12 VDC to 120 VAC, the primary has a center tap. I
>removed the output transformer and replaced it with the neon 24 turn center
>tap primary.
>I connected the car battery and it works. I get HV out of the neon. I
>don't have it connected to a TC but I get an arc across the output like I
>did before. I don't have any way to check the voltage either. The voltage
>is probably close, plus or minus a few hundred volts.
>
>I also discovered that you can not build a DC to AC converter using SCR's.
>It won't work. When the SCR is triggered it won't open again until the
>power it turned off. After about 2 seconds every solder connection melted
>and the entire circuit fell apart into a pile of parts on the work bench.
I
>didn't know what happened the first time so I soldered it all back together
>and did it again. Its a little funny, wish I had it on video tape, the
>circuit is soldered together one second, then all at once the entire thing
>falls apart all by itself. Look its magic.
>
>Gary Weaver
>
>