ISO Intertec 5.25" floppy drive jumper settings

Fred Cisin cisin at
Sun Dec 2 18:22:14 CST 2018

>> When they went to 400K 40 cylinder MFM DSDD / double sided, double 
>> density, still 48 tpi (like the PC-DOS 360K), they chose to call that 
>> "QD" / "QUAD DENSITY"!! ?!??  (equating "density" with capacity) WHOA! 
>> Everybody else called THAT DSDD "Double Sided Double Density", and used 
>> "QD" / "Quad Density" to refer to 80 cylinder Double density 96tpi!
On Mon, 3 Dec 2018, Adrian Graham via cctalk wrote:
> So I’ve been reading :) I’m sure they weren’t doing it deliberately, hahaha.

It's hard to say.  At NCC, at the Intertec booth, they could not 
understand WHY anybody would want to transfer files between disk formats, 
other than to PIRATE their "proprietary software"!  They even threatened 
to sue me if I included it in XenoCopy!
So, they were not heavy into interoperability with other brands.
That was the first time that I added a format to XenoCopy while in a hotel 
room.  (Televideo was the second!).  NCC was great.  In addition to 
those two formats, in exchange for buying him lunch, John Draper told 
me everything that I needed to know to add UCSD P-System formats - (I did 
NOT exercise with him.) 
Intertec did not keep their promise - I could have used the free ink.

> You’re right. Normally with Cumana stuff I do look for a manufacturer 
> because yes, they were known to me as makers of repackaged drives for 
> the Acorn BBC Micro. In this case the Intertec label is a bit of a red 
> herring and the drives are actually Tandon TM100-1 full height units. 
> I’ve got the manual from a Rat Shack related site.
> Thanks for making me look again :)

One more caveat!  Radio Shack repurposed pin 32 (SIDE SELECT) to use as 
their fourth drive select, and did their drive select with their cable, 
rather than the jumpers.  So did IBM, although they jumpered both drives 
as second drive, rather than ALL jumpered as RS had done.  IBM also used 
them, as well as the TM100-2 (DS), so there are a LOT of sources for the 

Grumpy Ol' Fred     		cisin at

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