Hi Max,
From my own experiments with a 7704A SMPS I remember that it needed a much heavier load for proper operation. I tried with loads on the HV outputs and also with loads on the raw rectified outputs (LV disconnected). Other members (including G?ran) found similar results. Dennis in his recent 7104/7854 .docx file uses 70 W total, distributed over the LV outputs. So why do you think about 35 W is enough?
I guess you also disconnected the supply to the HV unit? (Some other readers might not know that the HV unit is a separate unit here, not buried deep inside the smps box.)
It has been noted that the documentation of the control IC is not very trustworthy.
[BTW your 10W resistor will be glad that the smps is not working continuously!]
Albert
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I remember you all the actual scenario:
I'm working with only boards A23 and A12 connected together.
The low voltage regulator board A22 was disconnected from the rest of power
supply, and there are no other connections (I pulled out connectors P52,P50
and P54 from A12 board to better isolate the problem).
I've put a dummy load across +17 and -17V (connector P52) , 33 ohm resistor 10
W, I think it's a reasonable load for the SMPS to start.
Max
