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

["High Voltage list" <hvlist@xxxxxxxxxx>]

Original poster: <sroys@xxxxxxxxxxxxxxxxx>



---------- 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)

 
In a message dated 10/4/05 10:05:10 A.M. Eastern Daylight Time,  
hvlist@xxxxxxxxxx writes:


Someone suggested using a triode. I only know these as tubes from  amplifier
circuits. I've never heard of them being used as switches nor  anything about
their tolerance for high  voltages.

Thanks!

Jeff





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.
 
Hope this helps,
Matt D.