powesmith
2020-11-28 14:20:13 UTC
Happy Thanksgiving everyone. Could really use some help before I ive up and either buy a replacement PS board or have somebody take a look at the issue.
Starting from the end: the board blows F7 as soon as I turn the game on, with F7 blown I have +17VDC at the banded side of D5, -13VDC at the non-banded side of D7.TP for +12VDC, -12VDC, +5VDC all show proper voltage.
Right after the issue started, i started checking fuses and F7 was blown, the fuse holder for F7 was not the original and was in really bad shape. Literally fell apart when I took the fuse out. While checking the board TR3 and TR4 were blown which quite honestly was probably my doing when I was checking for voltages and my probe slipped.I rebuilt an entire HV section including C10, C11, D5, D7, D6, D8, TR1, D9, D11, D10, TR4, TR6. Didn't have a replacement for TR2, but it checks out fine.
I am at a loss but seeing as I don't have correct voltages at D5 and D7 is it possible that the issue is not with the PS board? DE Schematic is not the easiest to read but it looks like CN1 on PS goes straight to the transformer?
Any help will be appreciated.
Starting from the end: the board blows F7 as soon as I turn the game on, with F7 blown I have +17VDC at the banded side of D5, -13VDC at the non-banded side of D7.TP for +12VDC, -12VDC, +5VDC all show proper voltage.
Right after the issue started, i started checking fuses and F7 was blown, the fuse holder for F7 was not the original and was in really bad shape. Literally fell apart when I took the fuse out. While checking the board TR3 and TR4 were blown which quite honestly was probably my doing when I was checking for voltages and my probe slipped.I rebuilt an entire HV section including C10, C11, D5, D7, D6, D8, TR1, D9, D11, D10, TR4, TR6. Didn't have a replacement for TR2, but it checks out fine.
I am at a loss but seeing as I don't have correct voltages at D5 and D7 is it possible that the issue is not with the PS board? DE Schematic is not the easiest to read but it looks like CN1 on PS goes straight to the transformer?
Any help will be appreciated.