In article <54oqcf$ltr@ns1-1.CC.Lehigh.EDU>, <c002@Lehigh.EDU> writes:
> I need to drive a powerfull flashtube.  I have neither a tube or driver btw
> (ie: if you have, i'll buy! )
> This will be exciting a Ruby rod, so its not a little camera flash i need! 

We excited a Neodymium rod using two linear flash tubes and a HV power supply.
The supply was a 2000 volt transformer with an array of high-voltage 
capacitors and high-voltage diodes.

We stacked up five 450 volt capacitors on either leg of the supply, with 10Meg 
resistors across each capacitor to even out the voltage loading.  We also put 
10Meg resistors across each 1KV diode to protect it.

<bad ASCII art attempt:>

115V     2000V
----3 || E--->|-->|-->|-->|------\       [trigger circuit]
    3 || E                        \      /
    3 || E    ||--||--||--||--||-------O  O---------------\
    3 || E---<                                            |
    3 || E    ||--||--||--||--||------------[==========]--/
    3 || E                        /          Flash Tube
----3 || E---|<--|<--|<--|<------/

MAKE SURE THE CAPACITOR POLARITY IS CORRECT, or you will get big explosions of 
toxic oil.

We fired this sucker by an air-gap switch.  Basically you set the tube up with 
two metal spheres in the circuit, seperated by about 1/4 inch.  Then you use a 
photo-flash trigger coil connected to a wire probe between the spheres to 
ionize the air.  BAM!

Warning:  we blew chunks of metal out of a lead block with this device.  Be 
VERY careful when you set it up!

1.  Capacitors can maintain a fatal charge for a long time after the power is 
removed.  We shorted 'em out with a copper rod on the end of a Lucite handle 
before touching anything.

2.  Air-gap switches can fire spontaneously.  Never energize the device until 
everything else is ready to go!  We eventually went to an oil-quenched knife 
switch for more control.








Date: Sun, 27 Oct 96 21:09:26 PDT

Original Subject: Re: flashtube driver needed!!!!


Comment on this article


Comments on this article


This article is referenced in the following indexes: