If the heads are still good [1], these drives can often be repaired. I have unofficial schematics for the FC9 and FC16 logic boards in front of me... Something is sort-of telling me that the 9122C/D is a high density unit. You might get the drive to work, you might not. I have pinouts for some of these connectors : The 26 pin one (FC9, FC16 PCB) 1 Motor On/ --o o-- DS0/ Disk Chagne/ --o o-- DS1/ Change Rst/ --o o-- Step Direction/ Gnd --o o-- Step/ Gnd --o o-- Write Data/ Gnd --o o-- Write Gate/ Gnd --o o-- Head Load/ Gnd --o o-- Side Sel/ Gnd --o o-- Index/ Gnd --o o-- Track 00/ Gnd --o o-- Write Prot/ Gnd --o o-- Read Data/ Gnd --o o-- Ready/ Note that the DSn/ lines are binary encoded, not 1-of-n as on most other drives! This may not matter on a single-drive system. Power : 1 o-- +5V o-- Gnd o-- Gnd o-- +12V I have a pinout for a version of the 34 pin connector, used on the MP=-F52W-50 drive (FC26 PCB). I don't know if this applies to your unit (this drive is a double-density unit), but here you are anyway. 1 Change Reset/ --o o-- Dosk Change/ +5V --o o-- LED/ +5V --o o-- DS3/ +5V --o o-- Index/ +5V --o o-- DS0/ +5V --o o-- DS1/ Gnd --o o-- DS2/ Gnd --o o-- Motor On/ Gnd --o o-- Step Dir/ Gnd --o o-- Step/ Gnd --o o-- Write Data/ Gnd --o o-- Write Gate/ Gnd --o o-- Track 00/ Gnd --o o-- Write Prot/ +12V --o o-- Read Data/ +12V --o o-- Side Sel/ +12V --o o-- Ready/ Note that there are _many_ soldered links on this PCB. You can swap round the functions of pins 2 and 34, you can make all the odd-numbered pins ground (and have a separate 4 pin power connector), add motorised eject (with the input on pin 1) etc, etc, etc. The pinout I've given corresponds to the drive used in the HP9114B. Hope that is of some use to you -tony