Yamaha FD-03 with problems

Supporter (11)

26-01-2021, 22:46

Hi all

I've just bought an FD-03 disk drive and interface as part of a collection of Yamaha MSX machines. It was sold as not working but I was hoping to bring it back to life. I was hoping it might something simple like a drive belt. However in truth I was buying it at least as much for the look of it as the function and it definitely does look the part with the computers.

It looks cosmetically in perfect condition and powers up OK. However when trying to access a disk very little happens. The 'busy' light flashes on and goes out quickly, but the motor doesn't appear to run at all and the computer reports 'I/O error'.

There is a built in drive checker routine ('call drivecheck') and this reports an error code of 128 but I can't find any documentation anywhere about what these codes mean.

I've stripped the drive down, and it looks in pretty much perfect condition with no obvious signs of damage anywhere although I need to have a closer look at the capacitors. At the moment the plan is to reseat all the connectors (there are quite a few) and clean everything up in case something's got jolted somewhere. I've not done this yet though and it's all still in pieces.

Does anyone know anything about these or what the fault might be? I have found a service manual but it doesn't tell you anything about the error codes and there's no fault-finding guide as such.

Very grateful for any thoughts or advice (including "give up"!)

James

By st1mpy

Hero (662)

27-01-2021, 02:29

May be check the power supply as well with a volt meter to see its giving the correct value.
Is it a single sided 1dd drive? Have you inserted a suitable disk? (Covering one of the holes if using a 2hd disk).
If you use an old disk it may also have gone off.
I assume it has a standard size floppy drive unit inside, then try just replacing that with a working one to see if it is the drive that is faulty. If its not the drive, then its the controller cart or cable etc that is faulty.
In my opinion a 1dd drive is not that useful, it would be nice to upgrade to a 2dd, or put a floppy emulator inside like gotek (there are other choices too).

By Alexey

Guardian (2982)

27-01-2021, 09:21

Check both voltages on the drive's power connector. Check the continuity of all interface wires. Try to find what the error code means. Maybe the manuals from later drive models could be helpful.

By gw0udm

Supporter (11)

31-01-2021, 00:17

Thanks all. I have had no success finding out about the drive error codes. The technical manual doesn't even mention the self test routine. The drive itself also is nothing like I have ever seen with non-standard ribbon connector so I can't test it with another drive.

I am confident that the power supply is OK, I have tried a few different ones.

It is all still in bits at the moment, I am still hoping that cleaning it all up and checking the connectors will get me somewhere!

I know 1DD is not useful although I am more interested it a matching piece of hardware rather than its function!

Thanks for the advice

James

By gw0udm

Supporter (11)

04-02-2021, 20:10

I have made a bit of progress with this drive. I stripped it down, cleaned everything in sight and after putting it back together it does now work... most of the time. The motor runs, and when I try to access the drive sometimes it spins up and reads everything perfectly but at other times the motor doesn't start.

It seems to have got a bit better since I've been using it, any ideas on why this might happen? Could it just be a sticky motor?

James

By Jipe

Paragon (1434)

05-02-2021, 09:57

with a similary model in past i have a problem with the carriage head
just cleaned the old grease and put new ones