It just ran off DC for a whole day, literally 24 hours. Stayed cool as a cucumber. The supply was about 16 volts with 1 volt of ripple, mainly sawtooth.
Next I go one of two ways, either inject the DC onto where they put it off the transformer, like at the thermal cutout, without external filtering, or to disconnect the load from the transformer and plug it in and see if it gets hot. I think the voltage was a bit low, but I attributed that to low line voltage. Maybe not. I might have a bad transformer.
I think internally is has 2 X 1,300 uF for filtering, I'll leave the external 10,000 uF out of the circuit and see how much ripple I get. It should be the same and put that question to rest.
On yours I have been thinking, a better mounting arrangement can be had. there are holes for the base and emitter leads, or wires pigtailed off them, and the bolt will take care of the collector. I would put put them on the metal side, which I think is flat and should have more room than the PC board side. I'll look at mine one more time and figure out a good replacement. Now I am thinking maybe the ft is maybe not that critical, with it switching at such a low frequency, 3 MHz might be fine, not sure.
That driver transformer might only show 3 volts DC going to the primary but there is obviously a pulse involved. Since I'm sure mine switches right and I again have the bench space I can get some relevant waveforms. So figure out which ones you want or think you will need and I'll add in the ones I think will help and I'll get them fairly soon. I now have my own camera again so I don't have to borrow one anymore. It is actually not as good a camera as the one I had been borrowing but it seems to have more lens range in the way of going wide and the macro function. It's only 5.1 megapixels but I downsize pictures anyway so they don't take forever to load. It will do.
I think I am going to modify my bench power supply to go up to 3 amps instead of 2, this thing pulls about 2.3 amps, sometimes less. It's a damn shame not to be able to have a nice ripple free supply because of 300 stinkin' mA.
Jeff Urban