MFM or ESDI QBUS controller for one PDP-11/23 PLUS

Jerome Fine replies: Then perhaps you can describe your other hardware - backplane with power supply. Do you have a BA23 or a BA11 box? Or something else? What about the serial ports, etc.? I agree that the RQDX1, RQDX2 and RQDX3 require a distribution panel of some sort to change from the 50 pin cable to the 34 pin / 20 pin cable required by MFM hard drives and floppy drives. That panel is usually part of a BA23 box. A BA123 box uses a distribution board which can handle 4 drives, but the hard drives also require an additional READY / WRITE PROTECT (very small) panel. As far as I can remember, the only controller that I have ever used with an RX33 was a DEC "late firmware RQDX3" as Allison has noted. Probably a 3rd party controller like the Dilog DM01 is what you are looking for. But I suspect that these days, an RQDX3 is probably more easily found - except for that internal distribution panel which is also required if you are using a BA11 box. Let us know about your other hardware so that we can help a bit more. Sincerely yours, Jerome Fine -- If you attempted to send a reply and the original e-mail address has been discontinued due a high volume of junk e-mail, then the semi-permanent e-mail address can be obtained by replacing the four characters preceding the 'at' with the four digits of the current year.