Thyratron switched coils

From:  R M Craven [SMTP:craven-at-globalnet.co.uk]
Sent:  Sunday, April 19, 1998 3:30 PM
To:  Tesla List
Subject:  Fw: Thyratron switched coils

>>From:  Paul & Stephanie Miller [SMTP:smiller-at-rconnect-dot-com]
>>Sent:  Friday, April 17, 1998 9:34 PM
>>To:  Tesla List
>>Subject:  Thyratron switched coils
>>I'm gathering parts to build my first coil and among what I have so
>>are a 5C22 thratron and a CX1159 thyratron so I am looking for any
>>on tube switched coils, I probably won't use them on my first coil
>>maybe on my second or third or.................
>Further to recent comments on 5C22s, here are some details published
>by EEV.
>5C22 is equivalnced by EEV type 8503: this is a glass envelope triode
>H thyratron which has a peak anode current of 325A, average anode
>current of 250mA (0.25A), peak forward V of 16kV, heating factor of
>3.9E9, and heater requirements of 10.6A at 6.3V.
>The CX1159 glass envelope tetrode H thyratron, according to EEV, is
>capable of switching a peak anode current of 1kAbut the average
>current can only be 1.25A. Maximum holdoff is 33kV.
>The heating factor is 14E9 and the heater requirements are  22A at
>According to p 201 of Sarjeant and Dollinger, the heating factor is
>calculated from peak Vpeak x Ipeak x PRF
>but devices can be run in excess of this. The book quotes a CX1159
>being run at 30 times the value suggested by the heating factor.
>Remeber that it is the average current that will likely destroy the
>device. The rate of change of current in TC primaries will not damage
>H thyratrons.
>Richard Craven, Malvern, England