1/2 height 5.25" floppy drives (was: BASF)

[Chuck Guzis]

On 26 Sep 2008 at 19:04, Teo Zenios wrote:

> I think Epson and canon did also, I know I have atleast 2 different makes of 
> those combo drives.

The Teac FD-505 was the "combo" drive; an FD-05 3.5" drive 
piggybacked on a FD-155 5.25" slimline drive.  A 26-position 
connector on the PCB of the 155 allowed the FD-05 to feed into the 
regular 34-pin connector.   We did a setup of about 30 units that 
involved modifying the 505 for 3.5" 360 RPM operation (like a FD-
235HG tri-mode drive) and mounting it in an external drive box 
connecting to the external connector on a Compaticard so that the 
customer could handle 1.3MB 5.25" and 3.5" diskettes on their 
systems.

Epson definitely made "combo" drives as did Matsushita. As with all 
Teac drives, there are various versions of these, differing in 
mechanical and electrical implementations.  In particular, the button 
on the 3.5" FD-05 part changed its style and location somewhat.

I believe that Epson also made a 3.5" floppy-with-CDROM unit in a 
half-height size also.

You don't see many isolated FD-155 slimlines in the West, but they 
weren't uncommon in Japan.

Someone had mentioned the FD-235J drive in another post.  You should 
be aware that there were two major versions of the PCB, the "old" 
(3533 IIRC) and the "new" (3531).  The big difference is that the 
3531 includes several more signals on pins that are simply ground 
signal returns on the "old" version.  I suspect this was to enable 
the 235J to operate in some of the NEC 9801 series systems.

Epson had the double drives, as did Matsushita. 

I didn't care for the 5.25" implementation mostly because it used the 
jacket of the 5.25" disk as a mechanical actuator when the disk was 
inserted.  While this works fine on a 3.5" rigid-jacket diskette, I'm 
not so sure about the wisdom of doing the same with a less-rigid 
5.25".

Cheers,
Chuck