1541 schematic needed for 1540050 pcb

Disk drives, Monitors, SuperCPU etc.
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1541 schematic needed for 1540050 pcb

Post by ViperSan » Tue Sep 26, 2017 9:15 pm

Hi ..perhaps one of you guys can help me here ...
There has been fairly extensive repair work already to the data lines on this floppy drive ..and I have fitted IC bases to all the large chips ..and most of the 74 logic devices...
I still cant get it to run ..
All the large chips cpu, pla, roms via and ram chips have been swapped out ..with no improvement ...
the floppy stilll runs its motor continuously ..and red led is permantly on ...
All data lines have been pin to pin checked for continuity ..and wire links added whenever a suspect trace found..
I'm now thinking re-set might be the reason..
problem is that this pcb revision appears to have been modded at manufacture and is not wired like other versions..
In truth I'm finding it difficult to find a schematic which is accurate for this revision..
These are the details :-
PCB No 1540050 1982 Rev C made in Japan
Can anyone point me at a schematic for this board ..
close isn't good enough ..and believe me I've tried a few.

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Re: 1541 schematic needed for 1540050 pcb

Post by eslapion » Wed Sep 27, 2017 2:08 am


It should be in this service manual : http://personalpages.tds.net/~rcarlsen/ ... (1985).pdf

However, when visiting Ray Carlsen's pages, I get a big warning from Google and Chrome that these pages apparently contain malware yet there isn't any executables.

AFAIK, PDF files can't contain virus or malwares.

The 1540050 may or may not carry a special modification described in the service manual.
Wealth, like happiness, is never attained directly. It comes as a by-product of providing a useful service. -Harland D. Sanders

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