[TenTec] Model 260 PSU problem

[Steve Hunt]

Folks,

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?

73,
Steve G3TXQ