PerSci 277 floppy drives

[Randy McLaughlin]

From: "Doc Shipley" <doc at mdrconsult.com>
Sent: Tuesday, March 15, 2005 2:26 PM
> Randy McLaughlin wrote:
>
>> From: "Doc Shipley" <doc at mdrconsult.com>
>>>
>>>   Looks like a standard 50-pin edge connector, yes.  After reading a 
>>> little in the owner's manual, it's MFM, dual density, so worst case I 
>>> should be able to run it on an older PC-based FDC, right?
>>
>>
>> The 277 is a fast repeat fast single sided floppy drive.
>>
>> The high-speed seek can be ignored but what can not be ignored is the 
>> track location.  Being a dual drive both heads move at the same time, 
>> this can confuse some software.
>>
>> Details on making a 34 to 50 pin cable can be found on my website.
>
>   I've looked at that, but I don't have access to crimpers.  Would the 
> line noise from a soldered strip-&-splice be excessive?

No problem with soldering, for crimping IDC connectors: before I got a 
crimper I used vises, for a vise with metal jaws I put in blocks of wood for 
cushioning.

>   By the way, both your site and Herb Johnson's have been very helpful 
> already.  Thanks!
>
>> The Persci's also have a slew of jumpers, it is best just to try it the 
>> way it is.
>
>   So I've read.  I also gathered that the jumpers are soldered 0-ohm 
> resistors, not shunt blocks.  Correct?

On the Persci I hade it just used bare solid wire, a 0-ohm resister will 
work OK also.

>> The Persci's are very sensative, shipping often destroys them.  To ship 
>> it you need a special cardboard shipping retainer to keep the heads from 
>> slamming back and forth.
>
>   It shipped with the retainer in place.  And the original packing, and 2 
> thick binders of documentation.
>
>   I wondered why he shipped it with only one insert, but if both heads 
> move in concert, that makes more sense.

>From the factory it only came with one, when you retain one head the other 
is held by the same yoke.

>> It also uses special wheat-lamps that burn out easily.
>
>   Uhhh.  Are there replacements available?
>
>   Given the 277's temperament, I suppose I also need to see if the PerSci 
> 1070 will drive non-PerSci drives....

S100 disk controllers are easy to get, Herb sells them.  A Persci controller 
should work just fine with any SA800 drive but may require software changes 
and maybe one jumper (-TEST on 179X controllers).

> Doc

Randy
www.s100-manuals.com