• Please review our updated Terms and Rules here

Controller-board from unknown 5-1/4 floppy-drive, can anyone identify?

G

GearTechWolf

Experienced Member
Joined
Apr 24, 2015
Messages
264
Location
Washington
I think I've had this board (and most of its peripherals- sensors, head-motor, heads) since I was in the single-digits of age, back when I thought smacking circuit-boards with a hammer was great fun.
Now I'm much wiser and I'm trying to repair this board (plus the two controller-boards from a ST4038, but those are much more damaged) and aside from the missing chips (which I've replaced with sockets, including a couple trace-repairs) I'm now at a stand-still.
I don't know what the missing transistor at Q1 is supposed to be, the value of the rectangular capacitor at C8, the value of R27, nor what used to go at the space marked 220/330. (although I think it may have been a block of config switches?)
Board is marked ASSY. 900053-00(6?) REV D (silkscreen with faded hand-written 6 and D over white blocks) on top, and 0984 001 (date-stamp?) FRVO 900052-001-G (etched copper) on the bottom. There are no further markings.
Head stepper/servo is a SANKYO SEIKI MFG. CO., LTD NO. (BLANK) JAPAN TYPE MSHF200B71 VOLT DC[12]V motor with five wires on a six-wire connector.
Head assembly is stamped 24 JUL 1984 and has a sticker that says AMI 39456.
Head optical limit-sensor assembly is stamped 8423 (date?) MEXICO on one side and HOA6035-1 on the other.
The two optical disk-detection assemblies are unmarked, or at least have no surviving marks on the remaining plastic mounts.
The UCN4202ABU chip (spindle-driver?) is cracked at the corner by its 16th pin and may or may not be still functional.
The board is missing the MC3470A, MC3471, 74LS08, and two 7438 chips due to their destruction.
There is a 74LS04N in a location designated for a 74LS74 according to the silkscreen, it came this way from the factory.
It also has two UDN5711 MBU where the silkscreen calls for a pair of 75476's, also apparently as-factory.
Any help identifying this unit and/or pics of an intact board would be much appreciated!
Here's the pics: 5inchfloppy-1.png5inchfloppy-2.png5inchfloppy-3.png5inchfloppy-4.png5inchfloppy-5.png5inchfloppy-6.png5inchfloppy-7.png5inchfloppy-8.png
Underside pics in second post.
 
Sounds a little like a recent epiphany I had with a 5.25 drive that was in my scrap box for 25 years. A couple years ago I moved it out of the box, and more recently decided I wanted to get it working. Luckily all I removed from it was a not very important metal shield on top and some capacitors that I was able to replace.

As for yours, I think pictures of the rest of the pieces would help, especially the front bezel and even lever. I can't tell much from your pictures other than it's not a Chinon FR-506 and not a TEAC 55GFR like I have.
 
I might be able to identify it, but someone's hacked in a bunch of DIP sockets, so it's hard to tell. Certainly form a half-height drive, however.
 
jrmymllr said:
As for yours, I think pictures of the rest of the pieces would help, especially the front bezel and even lever. I can't tell much from your pictures other than it's not a Chinon FR-506 and not a TEAC 55GFR like I have.
Click to expand...
Unfortunately, I don't have much more than the electronic components, minus the main spindle. But I'll get pics of those too.
Got a ton of TEAC drives in worse shape after they got damp in storage, but at least they're complete.
Might steal the body/frame/bezel, disk-loading mechanism (and maybe the spindle?) from one of those and see if I can hack it to fit these parts.
Chuck(G) said:
I might be able to identify it, but someone's hacked in a bunch of DIP sockets, so it's hard to tell. Certainly form a half-height drive, however.
Click to expand...
That was me, figured I'd use up some single-wipe sockets on this long-shot project. How are they interfering with identification?
The silkscreen for what chips are supposed to go in those spots is clearly marked on the underside, and listed in the text.
I should've taken pictures before placing the sockets, but given how much of a pain it was to clean out all the holes with solder-braid before installing the sockets, I'm not going to remove them until I have a hot-air station, sorry.
 
You must log in or register to reply here.
Back
Top