[Coco] Floppy drive problem need help

[Charlie]

I am having a problem with a floppy drive I purchased from Cloud-9 a while 
ago. It is an ALPS Electric Co.
Model DFC222B02A. I purchased it as new old stock.

The problem is that when using a Tandy FD-502 disk controller the Alps drive 
will not DSKINI under RSDOS
or boot Nitros9, when it is used with another drive on the system. When it 
is used by itself it works fine.

Normally this Alps drive is my drive 0 and I have an IBM XT drive (YD-580) 
as drive 1. With a Disto SCII
these drives work fine together. When I use a FD-502 the Alps will not work 
as described above.

I have tried different Coco 3s, different ribbon cables, I even moved the 
Alps drive to drive 1 and it acted the
same. Still the same problems. I have a Panasonic 360K drive. I tried it 
with the Alps drive and had the
same problems. When I removed the Alps drive and used the Panasonic and the 
IBM XT drive together everything
works fine.

So to be exact, I can't use this drive in a two drive system. With all the 
swapping and testing I am able to do it can
be nothing other than the drive. What gets me is why it works with another 
drive using a Disto SCII and I only have these
problems with a FD-502 controller.

The Panasonic drive belongs in my Win98 PC I use to make CoCo disks, so this 
will leave my coco with a single drive.
Does anyone have ideas about what the problem is or should I start looking 
for another IBM XT YD-580 and forget about
this Alps drive?

Thanks!

-Charlie