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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: melott on October 17, 2003, 11:11:28 PM

Title: External Hard drives
Post by: melott on October 17, 2003, 11:11:28 PM
Anyone having a problem with external hard drives
spinning up??

I have an A3kd with the 25 pin scsi port on the back.
Lately I've had a problem with my external drive
spinning up. I'm sure its not the drive because I've
tried a couple other drives and same problem.
I'm wondering if the voltage that signals the drive
to spin up is marginal . I want to install a larger
drive but its not wanting to spin up and I'm sure
the drive is OK. I had the problem awhile back
and I switched the cable from a 24 in. to an 18 in.
cable and that seemed to work.
I'm guessing the voltage is low but what can I do
about it??
Anyone know anything about this??

Mel Ott
 :-?  :-?
Title: Re: External Hard drives
Post by: Tekoneiric on October 18, 2003, 12:21:19 AM
I have a 3k with an external SCSI box. I don't have any problems.

You might try to get a internal to 25pin SCSI adapter and use it to connect the external SCSI cable to the internal one on your SCSI box. See if you have the same problems.

If I were home I would try to dig up my 3K schematics and look around the SCSI section to get an idea of what it could be.

Andrea
Title: Re: External Hard drives
Post by: melott on October 18, 2003, 03:41:50 AM
That was discussed in an earlier thread.....
There is a set of terminators on the MoBo that
won't let the port work more than a few inches
from the connector.
I had done exactly that, connected a ribbon cable
to a 50 pin external bracket but it only worked
with a short (about 12 inches) ribbon cable.
I have seen things written on SCSI where they
use up to 50 foot cables. They must have a way
to boost the signals on a cable that long.
If I can find a pin-out on the external scsi port
then maybe I can figure out what can be done.
Still looking.........

Mel Ott
 :-?  :-?
Title: Re: External Hard drives
Post by: whoosh777 on October 18, 2003, 04:03:53 AM

My Blizzard 1230-II SCSI interface one day stopped functioning,
ie no booting. By using my SquirrelSCSI interface via the
PCMCIA slot I knew the drives were functioning correctly,

Eventually I opened up my A1200, and when I removed the floppy
drive to see the SCSI interface thing I found why the interface
was not functioning: an internal ribbon cable had become
detached from its position. So it was just a matter of reconnecting
the ribbon socket firmly and everything was back in action.

This of course may not be the cause of your own problem,

Have you got 2 SCSI interfaces?

If so you could then determine if the problem is with the
drive or the interface,

alternatively connect your drives to a different machine with
SCSI,

One other remotely possible idea: could the problem be with
your external cable, have you tried buying a brand new high
quality SCSI cable and seeing if it now functions?

:maybe your cable has got degraded somehow,

someone once told me that most SCSI problems are cable problems,
so its worth studying all cables involved,