It's turning into "one of those weeks"!
I couldn't understand why my new Omni VI was "unhappy" at full power when fed
from my Model 260 PSU, but was fine on the Hercules II supply. I just had a
look with the 'scope at the 13.8v line from the PSU. At anything approaching
full load there was several volts of ripple.
A bit more fault finding and it turns out the main diode bridge is open circuit
on one side; the clue was that I was seeing 50Hz ripple, not the 100Hz you
would expect from a full wave bridge circuit.
The faulty part is a "Varo R207T". TenTec would probably carry a spare, but it
seems a bit unnecessary to ship from the US if I can find a suitable
alternative here in the UK. But I can't find any reference to the R207T through
Google and so don't know what the spec is.
My local electronics store has a KBPC3504 rated at 400V PIV, 35A Ifavg, and
400A surge current costing just £1.60. It's the wrong case style but it would
be no problem to fit it on the same heat sink.
Any views from listers whether this would be a suitable replacement?
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