RL02 weirdness

[Aaron Jackson]

> On Sun, Dec 17, 2017 at 5:04 PM, Aaron Jackson via cctalk
> <cctalk at classiccmp.org> wrote:
>> Now that I have my RX02 drive working I have started to take a look at
>> the RL02 drives again. I hooked a scope up to the sector transducer and
>> sector timing test points, and they look nicely aligned. So I moved on.
>>
>> Then I hooked up the scope to the TP1, TP2 and the sector timing TP and
>> compared it to the output in the RL02 tech manual. S1 was fine but S2
>> was offset in the wrong direction (probably need to see page 3-8 in the
>> manual to understand). I had a look at where the heads are connected to
>> at up was connected to down and down was connected to up.
>
> I wonder if you fell into the 'trap for the unwary' here. The heads are named by
> the direction they face. So the upper head, nearest the top of the drive, is
> the 'down' had as it faces down onto the platter. Similarly the lower
> head is the
> 'up' head. Yes, it confused me at first,
>

I'm not sure, because the labels on the female connector says up or
down, as does the circuit board. So I connected them so up->up and
down->down, which resulted in this crash. So maybe the person who used
it before me fell into the trap you mention, failed to get it to work,
and then ended up with me in a none-working state?

>>
>> Without understanding the consequences I switched these and loaded a
>> pack. Unfortunately I heard a horrible sound and I now have a thin black
>> ring on the bottom side of my platter, which I am very upset about. :( I
>> unloaded very quickly but I think the damage is done.
>>
>> Why would the heads be installed this way? and why did it destroy my
>> platter when they are connected "correctly"?
>>
>> Does anyone understand what might have happened?
>>
>> Thanks, and sorry for destroying a pack :(
>
> My first worry is that you have damaged the heads as well as the pack.

Possibly, although I hope not. The head looks okay but perhaps the
damage is invisible.

>
> I am not sure why this caused a headcrash. It shouldn't have done.
>
> -tony

I have a second drive which I am willing to use for parts, but only if I
am certain it won't damage something else.

Thanks,
Aaron.