Date: Thu, 4 Jun 2009 15:52:40 -0400
Subject: Re: For pickup: VAX-11/750 and RK07
From: ethan.dicks at
gmail.com
To: cctalk at
classiccmp.org
On Thu, Jun 4, 2009 at 3:26 PM, e.stiebler wrote:
Patrick Finnegan wrote:
And, they've been claimed.
That was fast.
Yes, I can imagine. I gave mine away, and now I'm missing it ;-)
Indeed. 15 years ago, I was able to save the 11/750 from work, but
could not find room for a pair of RK07s and a pickup-truck-load of
RK07 cartridges. Those were good drives - easy to repair, decent
amount of storage for the day, fast. Just don't get your fingers
behind the ears on the voice coil during a power-down - those heads
snap back *fast*! (when the NiCd pack is good, that is).
Someone just got a fun little system to play with. Hopefully we'll
hear what it's running and how it's loaded before too long.
-ethan
Definitely good advice to keep your fingers away from the heads
and carriage near the voice coil! I have a movie clip on my site
showing the loading of the heads on an RK07. Moving in *fast* from the
rest position (far rear) to track 00 and then slowish to the inner
track and then back to track 00. After that the READY light will lit.
The movement from the far rear to the edge of the platter is quite
fast ... But I wanted to see what would happen if you disconnect the
head that reads the servo track ... pity that I do not have a movie
of that, but I sure don't want to repeat that just for a movie.
The heads move from the far rear at full speed all the way to the
inner track and then at that same fast speed back outward.
Having your fingers there would certainly hurt a lot. Now, without
control, just by NiCad pack at brute force, I can imagine that the
movement will be even more deadly for your fingers.
If you have an RK07 drive, open the rear top lid, use a piece of wood
to push down the lock mechanism of the head carriage and carefully
try to pull the heads out of their far rear position. If the NiCads
are still OK, you will need a lot of force the moment the microswitch
clicks. At that point I stopped. I don't know how good the NiCads in
that drive are (still need to check that), but it was impressive.
I guess the RK05 will behave similar with a good NiCad pack.
I have five (!) RK07 drives. I want to keep 3 of them, so sooner or
later two drives will have to go (in The Netherlands).
I plan to connect them all to the RK07 Field Test Box to see in what
shape they are. They should all be OK ...
- Henk.