amadain
Member
Hi,
I'm trying to revive an XT with dual Tandon TM-100-2A floppy drives. The XT boots and I can run DOS(3.3). One Tandon works fine, if a little noisily. When the other is connected to the PC PSU the PSU refuses to start. I assume it is the protection against a short kicking in. The dud drive works fine if the main logic board of the working drive is fitted to it.
Resistance measurements, with a cheap DVM, between pins 1 & 2 - the 12V supply, I believe - of the Molex power connector of the faulty main logic board appear to show virtually zero resistance. I have a copy of the Sams TM-100 Computerfacts booklet. However my electronics knowledge and reading of schematics are not great. I suspect a shorted capacitor in the early part of the power supply circuits of the main logic board.
Am I way off base in this assumption? I would be greatful for any hints of where to look to find the problem.
T.I.A.
Simon
I'm trying to revive an XT with dual Tandon TM-100-2A floppy drives. The XT boots and I can run DOS(3.3). One Tandon works fine, if a little noisily. When the other is connected to the PC PSU the PSU refuses to start. I assume it is the protection against a short kicking in. The dud drive works fine if the main logic board of the working drive is fitted to it.
Resistance measurements, with a cheap DVM, between pins 1 & 2 - the 12V supply, I believe - of the Molex power connector of the faulty main logic board appear to show virtually zero resistance. I have a copy of the Sams TM-100 Computerfacts booklet. However my electronics knowledge and reading of schematics are not great. I suspect a shorted capacitor in the early part of the power supply circuits of the main logic board.
Am I way off base in this assumption? I would be greatful for any hints of where to look to find the problem.
T.I.A.
Simon