10 Apr
2007
10 Apr
'07
1:17 p.m.
RD53s are notoriously unreliable, but I'm
surprised that four out
of five simply aren't detected. Are they genuine DEC RD53s? You
need to add a PCB link to an ordinary Micropolis 1325 or 1335 drive
to make it an RD53. Look on the PCB for the location marked R7
(remove two screws and carefully hinge it up) -- if there's nothing
there, solder a link in that position. Oh, and don't use a skid
plate with bare metal with an RD53, as it can short things out.
Three of the four failing drives were official DEC RD53 drives as
indicated by a sticker on the top. Interestingly, when Iooked at R7
on the PCB, two of them had the resistor present but one end had been
cut. I soldered it back together but both drives still fail. At least
one of the drives spins up but then back down again. I'm reluctant to
try swapping the PCB between my only working drive and one of the bad
ones so I think I'll just count them as a loss.