Re: SFD-1001 Repair Question

On 5/31/20 8:24 PM, vtgearhead wrote:
> By swapping in a 6530 from a CBM 4040 drive, I confirmed a bad 6530 in the
> SFD1001.  With the substitute chip it passes the performance test
> diagnostic.  Encouraged by that I ordered a board based on Ruud's design to
> use a 6532 replacement.  For the first round I programmed the 1k binary
> image of 251257-02A.bin into the top 1k of a 2764 EPROM.  The drive gives 5
> flashes  (same as the original symptoms).  Next, I burned a 2764 with the 1k
> image repeated eight times.  The drive would now initialize and seems to
> read data - at least I can load and run "performance test" from the SFD
> diagnostics diskette.  However, the test fails at the first step (format
> scratch diskette).  Similarly I am unable to format diskettes from CBM Basic
> using 'HEADER"NAME",U8,D0,I42'.  In either case, it recalibrates to track 0
> and just sits there with no head step, eventually timing out with a disk
> error.  I have tried three or four diskettes that all worked with the
> replacement 6530.  No luck at all.  Does anyone have advice for the next
> troubleshooting step to take?  Is something different needed on the EPROM?

Just curious... Did you fix the leaking caps in the drive mechanics 
(spindle motor control board) of the SFD-1001 yet?

That is likely not your problem, but something that needs to be done.

  Gerrit