Troubleshooting and Repair: SpeedRite SB1000 Fence Charger

A friend sent me this malfunctioning fence charger module to see if I could get it working.

And I have done, sort of. I’m working without a schematic or parts list, without the HV output transformer and the pulse capacitor, but I’ve made substitutes for those parts which are probably adequate for testing. The unit is still not charging the capacitor properly although all other functions seem to be working as designed.

If anyone out there can provide me with a schematic with parts list, or even just the right part number for the Q2 transistor, that would be very much appreciated.
The transistor that I thought was a 2sc556b which triggers the SCR is actually a PNP, BC556B, a real cheapie. I’ve tried other pnps here but I can’t get them to pulse, although they do allow charging.

This is a SpeedRite SB1000 fence charger, originally made in 1994 or perhaps 1996.

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