Re: Q - Driving HV DC pulses? (fwd)

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Original poster: <sroys@xxxxxxxxxxxxxxxxx>



---------- Forwarded message ----------
Date: Wed, 05 Oct 2005 18:49:20 -0400
From: Jeff Bullock <jeff@xxxxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Q - Driving HV DC pulses? (fwd)

Hi Matt ,

Thanks for your reply.

> ---------- Forwarded message ----------
> Date: Tue, 4 Oct 2005 12:20:14 EDT
> From: Mddeming@xxxxxxx
> To: hvlist@xxxxxxxxxx
> Subject: Re: Q - Driving HV DC pulses? (fwd)

> Hi Jeff,
>
>     Yes, tubes can be and have been used as switches.  All of the earliest
> digital computers and radar systems were vacuum tube  devices. The first
> multivibrators were VT devices. Power handling  capabilities of a single
tube range
> from 1 mW to 50 KW. Plate voltages up to 10  KV are not uncommon for
> transmitter types.  For your application, you will  need one with a small
"knee" and
> steep slope.
>     I would recommend that you get a copy of RCA manual  TT-5 (reprints
from
> Antique Radio Supply, Tempe AZ) and a book on digital  circuits published
> 1942-1962.
> Perfect square waves do not exist in the real world. You can, however, get
> to the point where the rise and fall times are such a tiny fraction of the
> pulse  width that it looks square and works for most purposes.

Good info. Using tubes are not by any means a the best choice for this
application. Solid-state solutions are ideal. Tubes may, however, become
necessary to switch the high voltages quickly. BTW, it seems like the triac
is a close solid-state relative to the triode.

Regards,

Jeff