Quoted from Knxwledge:I've squared away my rectifier board on my Lost World (as of now), so I'm starting to move on to plugging the other boards in individually and verifying their voltages are good one by one. My solenoid driver board is giving me issues. All test points are good, except for TP2. TP2 is supposed to be 190vDC, adjustable by the trimmer pot RT1. Mine, however, tests consistently 240vDC, no matter what the trimmer pot is set at. It is the -22 revision of the board.
I recapped the board (including tantalum cap, upgraded C23 to a 15000uf cap), replaced both bottlecap transistors, reflowed the header pins, did the two suggested jumper mods (jumpered the negative lead of the cap C23 to the trace directly below it and tied TP1 and TP3 together), replaced Q23, replaced one of the diodes near the bottom of the board (CR8 IIRC, but that's not particularly relevant to this problem I don't think), replaced trimmer pot RT1.
I tested essentially everything in the 190vDC circuit, and I found that VR1 (the diode), R56, R35 and R54 all tested bad/out of spec. The fuse never blew.
My readings for Q22:
Red lead on base- c tests .64 and e tests .65
Black lead on base- c tests open, e tests 1.26
Black lead on c- e tests 1.25
Red lead on c- e tests open
My readings for Q23:
Red lead on base- c tests .64 and e tests .65
Black lead on base- c tests open, e tests open
Black lead on c- e tests .52
Red lead on c- e tests 1.03
Tests on Q22/Q23 were done within circuit, with the 4 parts I identified as bad earlier out of circuit (if it makes any difference). It seems to me that these are bad (even the one I just replaced).
Something I did notice is that from both Big Daddy and Marco, the cap that's supposed to be 360uf is sold as a 350uf. I'm assuming the 360uf isn't made anymore. Would this cause issues?
My plan was essentially to just shotgun replace the 6 parts that are bad, as well as the two 0.01uf 500v ceramic disc capacitors in the circuit. Is there anything else I should test or consider before going for this plan of action?
HV in = HV out usually means all three HV transistors are bad.
The 22k and/or 82k 1/2W resistor burn up when the transistors go bad. Can normally glance at a SDB and if you see the 22K or both resistors fried you can pretty much guarantee the HV section transistors are bad. The bally repair guide tells you to replace the 22k resistor if the if the HV transistors are bad, probably because it consistently burns up when the transistors fail.
HV in good but low HV out usually is bad zener diode.
The HV cap should be 150uF at 350v+ So i think you are probaby mixed up V rating with the uF rating. 360uF will be fine too as long as it is rated for over 350vdc.
