Rack-mount or tabletop version of DEC RX50 floppy drive?

[Ethan Dicks]

On Tue, Oct 2, 2018 at 6:50 PM Eric Smith via cctalk
<cctalk at classiccmp.org> wrote:
> Did DEC offer a rack-mount or tabletop box version of the RX50 floppy
> drive, as they did with e.g. the TU58 and TK50 tape drives?

Yes.

> I'm wondering
> how they expected the RX50 drive to be packaged when used with a Unibus
> PDP-11 via the RUX50 controller.

We had an external RX50 on our 11/750 at work (so we could cut
floppies for our MicroVAX customers right from our main machine).  The
box was the typical external DEC 5.25" drive box of the day, also used
for TK50 and RD5x drives - it could take a black sled, like the kind
used with the BA23, and had a PSU inside next to the drive.  In the
back was a transition board that was different depending on the drive
type, but typically had between 1 and 3 DD50-P connectors.  We had a
10' DD50P cable that went from the back of the drive box to an I/O
bulkhead plate on the 11/750, then an internal flat cable to the RUX50
controller.

I don't know the part number for the box, but with the cover off, they
looked like this:

https://thumbs.worthpoint.com/zoom/images3/1/0816/09/dec-vax-pdp-rd-tk-drive-shelf_1_2c22716c08caa3df496022a1cd806fce.jpg

(This one has the internal I/O board and cables for an RD5x drive.)

I happen to have at least 3 of these boxes, all have dead PSUs.
Nothing magical in them - 110/220 VAC inputs, and a single 4-pin Molex
drive connector with +12V and +5V outputs at a enough amps to drive a
TK50 or RD51.

We usually positioned the RX50 on top of the 11/750 next to the
console terminal so we could log in, fire off some DCL scripts and
make some floppies.   The cable would have let it sit on a nearby
table or in the next rack over, but not any further than that.

-ethan