Posted by Tnuctipun [ 172.158.130.208 ] on January 23, 2005 at 20:21:57:

In Reply to: Test Points posted by manualblock on January 22, 2005 at 21:10:15:

Hey-Hey!!!,
Damir has got the anticipated voltages pretty close. Go to the Duncan amps TDSL and get the data sheet for the 5687( probably have to get the 'WA' version, it's the same ).

Block off the curves past ~200 volts. Draw a horizontal line at ~10 mA. Interpolate a bit to generate a grid curve at ~3.7 volts. What plate voltage do the load and grid lines cross? By the curves in my sheet, it looks like ~90V. Perhaps a third LED to raise the plate voltage to ~120 might be a good idea...try both and see. You can clip lead a short of one of the LED's if you want to put in three the first time.
regards,
Douglas

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