I need to fix an igniter box, I suspect it might be the high voltage rectifier, what modern equivelent could I use for the rectifier diodes? The box is a rotax type NB 25/3, 24 volts in, 2kv out, 12 joules. It's a simple circuit comprising of a trembler mechanism, induction coil, rectifier, choke, reservoir cap, discharge gap. When I apply 24v, the trembler buzzes as normal but no high voltage. Any ideas?