Disk drive head locking (DEC RA-82 and HP 7920)

From: Andreas Freiherr <Andreas.Freiherr_at_Vishay.com>
Date: Tue Feb 11 05:26:00 2003

Some more hints interspersed...

Gooijen H wrote:
> Hi Dan.
...
> 4) In the middle yoy see the large (black) cilinder
> thing. That is the HDA. When you stand in front
> of the drive you see a small lever at "6 o clock".
> Rotate that level 180 degrees to lock the heads.
> You must lift the level at the end a little to be
> able to rotate it. On the HDA is a text that tells
> you the position of the level. (At least, that is
> the case with my *RA81*.

The RA82 is quite similar. I don't have one here to look at, but from
memory, you can follow the description on the HDA.

> 5) At the right hand side, near the chassis plate of
> the drive is a handle. This handle releases/sets
> the drive belt free/tension to the HDA.
> I do not know if the tension should be released
> when you transport the drive. If you are not going
> to use the drive for say, several months, you could
> release the tension to prevent deforming (flatten)
> the drive belt at one location.

Yes, always release belt tension when the drive is to be transported.

You may find four orange mounting brackets that are screwed to the HDA
at one end, with the other end hanging free in the air. These are
intended to bridge the rubber dampers that support the HDA while the
drive is transported, probably to avoid damage to the dampers.

> Take care, RA82's are heavy,

Yes! For this reason, DEC recommended to remove the HDA from the chassis
if you want to lift the drive. This can be done quite easily: release
belt tension, pull off the cable at the read amplifier board that is
mounted directly to the HDA, then undo the four screws that hold the HDA
and lift the HDA out vertically.

Take care to put down the HDA at the four pods on the *front* side,
never lay it down on it's bottom: you may damage the belt gear and the
bearings.

Mounting the HDA again does not require any adjustments, you may only
want to check belt tension after transporting.

The HDA accounts for about 16..17kg of the total weight (>50kg) of the
drive, so this helps a bit.

--
Andreas Freiherr
Vishay Semiconductor GmbH, Heilbronn, Germany
http://www.vishay.com
Received on Tue Feb 11 2003 - 05:26:00 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:35:54 BST