spencer@well.UUCP (Randal Spencer) (12/09/86)
This is just a little hit I got from the guys in the repair department at
my local Amiga store. If you have an NEC drive they take too much power
and will blow up the power supply if you hook more than one in a line.
However Amiga is now using Panasonic drives. There are two kinds, and the
new kind does pass the power on to the even more external drives (df2: on).
The way to tell if you have a Panasonic is by looking down it's throat.
The spindle that supports the disk will be one of two colors. Brass and
you have an NEC, brown and you have a Panasonic. If you look at your
internal drive and it also has a brown spindle than compare the internal
and the external. If either has a shorter spindle than that is the new
drive assembly that does pass the power to the further external drives,
if that one is the internal drive, you are out of luck. If you do have
a brown disk spindle and can't tell try plugging in your external brown
disk drive to the Amiga and another external disk drive (NEC will do) to
that. Power your Amiga back up and watch it loadWB. If you have a disk
in there and the Amiga says that it is bad than the power wasn't passed.
You see, even though the power to drive the motor isn't passed, the sense
lines still get through, and the drive light still lights, so the system
will recognize it, and it will look like it is going to work, but it will
not read disks (because it will not spin disks).
This is all in theroy because all they had at the Amiga store was Brass
drives, but if the Panasonics really don't take much power, I am going
to swap my internal and external drives and connect the power to the
further external drive so I can have 3 drives (four with the transformer
drive).
Things to remember: Every disk drive you attach eats more memory, so don't
try this unless you can afford the lost 20-30K. If the drive that you
attach to the end of the chain has a brass spindle (is an NEC) then you
should only do that as a test. There must be a reason that Amiga made it
so that you couldn't attach more than one drive back when they were using
NEC drives. If you use a Panasonic drive and an NEC you could blow your
power supply as quickly as if you used 2 NEC drives. If you are trying
this setup, and one of your drives is NEC, makes sure that it is the
last in the chain, as it won't pass the power (guarenteed). If you do
discover that you have two Panasonic drives (or have friends who have them)
and you plug an external drive into your external Panasonic and it does pass
the power and it does work. I would wait until Amiga has read this note
and has had time to reply before you start using this set up on a regular
basis. If it does pass the power supply than it does it for a reason,
so it should be safe, but nothing like hearing from the horses mouth.
Comments from grr? (love that site name)
--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Randy Spencer P.O. Box 4542 Berkeley CA 94704 (415)284-4740 ...well!spencer
I N F I N I T Y spencer@USCVAXQ.bitnet
Now working for |||||||||||::::... . . spencer@usc-oberon.arpa
But in no way |||||||||||||||::::.. .. . .
Officially representing ||||||||||||:::::... ..
s o f t w a r e
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-grr@cbmvax.cbm.UUCP (George Robbins) (12/10/86)
In article <2182@well.UUCP> spencer@well.UUCP (Randal Spencer) writes: >This is just a little hit I got from the guys in the repair department at >my local Amiga store. If you have an NEC drive they take too much power >and will blow up the power supply if you hook more than one in a line. >However Amiga is now using Panasonic drives. There are two kinds, and the >new kind does pass the power on to the even more external drives (df2: on). ... I would wait until Amiga has read this note >and has had time to reply before you start using this set up on a regular >basis. If it does pass the power supply than it does it for a reason, >so it should be safe, but nothing like hearing from the horses mouth. Sorry, I'm afraid this is just rationalization on the part of these service people. As I've explained at more length in another posting, the fact that some drives pass power and some don't is, shall we say, unplanned. As far as I know, any difference between the power requirements of the drives is incidental. There may even be a third qualified vendor, which would really confuse things, huh? Obviously, there is some room to play here, but you must decide whether you are a hacker or user, and whether you can put the pieces back together if you guess wrong... -- George Robbins - now working for, uucp: {ihnp4|seismo|rutgers}!cbmvax!grr but no way officially representing arpa: cbmvax!grr@seismo.css.GOV Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)