Ok, so I had an old TK50Z-GA that was marked "dead" and I ripped it apart
and discovered a couple of blow caps on the "heater" board :-) (some
adjunct to the PSU) replaced those and it seems to work somewhat again
(I've not hooked it up to SCSI, just powered it up to see the drive light up)
Anyway, I took my other drive that I was powering up on the bench and by
wiggling out the TK50 connector and the power connector I can now plug this
thing in an watch it in "real time."
This has yielded a bit more information about the failure mode of the
drive. With the cover removed I can watch what the drive is doing. This is
what I've found out.
The "hook up" leader was around the spool and out of the feed path. Now
when powered up the drive turns the spool a bit and then starts spinning it
making the leader thingy go whack whack whack on the edges. (DEC weed
whacker! :-) If I re-feed the take up lead through the tape path it moves
back and forth a bit and then stops with the red light flashing.
[Note to Tim: My test tape is a scratch tape]
Then I fed the tape in manually and hooked it up to the leader. Now the
tape was taken up on the spool a bit, then it rewinds to what might be the
load point and stops. Then the red button flashes. If I try the press and
release a few times leaving it in the unpressed position the drive feeds
some time then rewinds and stops just as the end of the actual tape
(beginning of the pick up lead) reaches the capstan.
[Reference Picture :
http://home.mcmanis.com/images/tk50-2.jpg ]
In the reference picture I circled in Orange where the leader stops and in
red where I cleaned with a q-tip. I've confirmed with my IR detector that
the LED in the lower right side of the picture (more toward the rear) is
emitting.
So several questions come to mind. I'll pop out some of the obvious ones...
1) Does the Red Light/Button on the right hand side in the "out" position
mean "unload" ?
2) When does the green light come on (except on power up when it is
unloaded.) ?
3) It appears that a "working" unload sequence would have the tape leader
get sucked back
into the tape and the 'unhooker' should engage the hook leader. Why
would it stop
before it got that far?
--Chuck
Received on Sat Feb 12 2000 - 20:03:50 GMT
