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Old 1st Jan 2010, 10:45 pm   #28
swordholder
Rest in Peace
 
Join Date: Aug 2009
Location: East Preston, Sussex
Posts: 162
Default Re: Homebrew Valve Tester

Howard,
Thanks for the comments, very much appreciated.
All the 15v zeners are the same (If I remember correctly 1W rating)
There is no bleed resistor in the anode circuit as the load resistor is the valve itself, no HT is applied until the fuctions switch is in the test position.
The meters I used are
200v DC for the Grid voltage
200mV DC for the anode current
200mV AC for the GM meter
I bought these from
http://stores.ebay.com/Runfunpower
Note these have to be run from separate 6v AC supplies or they will be damaged.
C10 is 100uF 63v
D6 is 1N4148
Hope this answers all your questions
Kind regards and a Happy New Year

Mike
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