On Tue, 04 Oct 2005 15:20:02 +1000, Franc Zabkar
wrote:

On Mon, 03 Oct 2005 14:05:55 +0100, Terry Pinnell
put finger to keyboard and
composed:

It may be coincidence, but I've only become aware of this since
installing a third HD - a 200GB Maxtor Diamond, 7200 rpm, in addition
to my two 60GB Maxtors.

I would think it unlikely that your two identical drives would spin at
a speed that is different enough to produce a 1Hz beat. That's a
difference of 1:120, or 1:360 if you consider a possible harmonic
effect of the motor's three windings. AFAIK, the speed is crystal
locked. Your observation in respect of the 200GB drive sounds more
plausible since it could involve different crystal frequencies.

-- Franc Zabkar

Please remove one 'i' from my address when replying by email.

Obviously, the near empty new drive is filled with a minimal amount of
data, located on one side of the platter. This causes a considerable
unbalance, causing vibration.
Just put more stuff on that drive.

And now I will go on with my design of a battery charger that cuts off
the charging process based on weight increase of a charged pack.


--
- René