From: "Terrell W. Fritz"
Date: Sun, 24 Mar 2002 14:45:59 -0700
Subject: Re: Ready :-)) - Re: [TSSP] short H/D and stuff
Hi Paul,
The arc shorts directly to ground. I have a 22nF cpa in parallel with the
spark gap just to make the circuit fire every few seconds and to stabalize the
voltage across the arc. but when the gap fires. It is all shorted to ground.
I'll post a diagram in the 3-24 directory in a few minutes.
Cheers,
Terry
At 09:28 PM 3/24/2002 +0000, you wrote:
>Hi Terry,
>
>There's only one possible doubt about this experiment - when
>the coil is pinged, the base is grounded not directly, but
>through the tank capacitor - 50pF I believe. With an equivalent
>shunt capacitance of only 10.65 pF at f1, this is enough to
>give a reasonable facsimile of a grounded base, but it does give
>some cause for concern. The predicted current profiles assume
>a firmly grounded base. The effect of this capacitive ground
>connection would be to raise the current max even further up the
>coil, and to increase the current at the max.
>
>Unfortunately I can't quickly reconfigure the model to check the
>effect of small series C in the ground connection. Can you specify
>just what the pinging circuit consists of, and is it possible to
>use a larger tank C for the impulse, say 500 pF? If Fres doesn't
>alter more than 1% on going from 50pF to 500pF I'd say the effect
>on the current profile would be neglectable. The fact that the
>model already gives a good account of the coil's resonances is
>encouraging, and means I'm probably worrying about nothing.
>
>--
>Paul Nicholson,
>--
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.