Fred Cisin cisin at xenosoft.com
Sun Apr 8 20:02:55 CDT 2018

> Should have left it the way it was and have people set the Drive Select
> themselves.
>> Radio Shack used a different approach to drive select by cable instead
>> of making use of the well documented drive select on the drive.
>> Radio shack jumpered all drive selects on on the drive, and pulled
>> pins in the cable.

On Sun, 8 Apr 2018, allison via cctalk wrote:
> OR used a straight cable and people used the drive select.

THAT's the approach if users are smart enough to read simple instructions 
and follow them.

SOME users, or store technicians, are not smart enough to handle it.
AND, PC dominated the market so thoroughly that some drives are shipped 
hardwired to PC jumpering, so for anything other than B:, it may be 
necessary to cut and solder to switch back to normal jumpers.

>> SMC 37C651.  Supports  500 Kb/s, 300 Kb/s and 250 Kb/s Data Rates.
>> Something else we lost with the PC.
> The 37C651 is 765 variant,  so any PC should be able to create a
> compatible disk.
> Least for my CP/M systems its never been an issue.  considering I'e used
> 8/5.25/3.5 drives
> on the same boxes it should not be a big deal.

Some excellent tips:
> Some notes:  The 37C651 and its kin all have minimal drive so long
> cables are
> out as they pick up noise.  Keep the cable away from monitor (crt based)
> and any
> switching power supplies.  Use a separate ground wire from the drive
> frame to
> the board ground.
> The IDE interface same deal, short cable only and one drive.  CF works.
> When making a disk first ERASE IT using a degausser then format and copy
> to it.
> Also make sure the drives are the same TPI, your trying to make life easier.
> I've had the best luck with older PC 5.25 like Toshiba and Teac.  For
> 3.5 Sony
> and Toshiba are the go to but if all else use the same drive to write it
> and read
> (that means moving it).
> One last detail make sure all the voltages (+5, +12,-12) are good and clean.

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