RD54 Stopped Spinning

[Robert Jarratt]

Bit of an update. I put the transistors back as they seem to be OK and
applied power to see if probing around would show anything. The Z8 was
getting power, and the transistors did heat up within a few seconds, but the
disk did not spin at all.  Is this going to be a problem with the motor
itself?

On a side note, I spotted a component which I can't identify, folded down
above the Z8 and stuck to what looks like an adhesive pad on the PCB. The
can looks a bit mottled/corroded. On another non-working RD54 it seems to be
marked "12039". I am not sure what this component is, although it looks like
it could be a capacitor. Anyone know what this might be?

Regards

Rob

> -----Original Message-----
> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Robert
> Jarratt
> Sent: 02 April 2015 23:19
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: RD54 Stopped Spinning
> 
> The other day my RD54 just stopped rotating, dead in its tracks, while it
was
> running. I guessed one of the motor control power transistors may have
failed. I
> assume they are the series of 6 chunky ones attached to a single heatsink.
I
> have desoldered them (en-masse) and tested them with a Peak
> DCA55 tester, and they all appear to be working. Does anyone have any
other
> suggestions? Has anyone ever repaired an RD54 control board?
> 
> 
> 
> Regards
> 
> 
> 
> Rob