fired it up .......
58ma stable, B+ at start was 335V soon to drop to 240V ....
dc offset was strange , both channels werent stable, one measured between 20-22mV and the other 76-80mV ... changing all the time ...
output cap leaking ? oscillation ?
at least no boom kaboom , no smokes ...
output cap similar to this one only 2uf (http://www.ebay.com/itm/MBGP-2-Pape...526&pid=100011&prg=1005&rk=1&sd=250906640986&)
58ma stable, B+ at start was 335V soon to drop to 240V ....
dc offset was strange , both channels werent stable, one measured between 20-22mV and the other 76-80mV ... changing all the time ...
output cap leaking ? oscillation ?
at least no boom kaboom , no smokes ...
output cap similar to this one only 2uf (http://www.ebay.com/itm/MBGP-2-Pape...526&pid=100011&prg=1005&rk=1&sd=250906640986&)
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How you got the sense and force wires hooked up? Can you describe or sketch the power and ground nodes they meet?
they are tied together along with cathode resistor ground / pot ground and ac mains earth ...
Maybe it draws much. Try boost the CCS at say 70mA to see if it holds before other investigations.
give me 5 min to report back ....
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