17 Dec
2017
17 Dec
'17
9:04 a.m.
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.
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 :(
Aaron.
17 Dec
17 Dec
9:28 a.m.
On 12/17/2017 12:04 PM, Aaron Jackson via cctalk 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.
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.
One turn thats all it takes.
Why would the heads be installed this way?
Error, accident.
and why did it destroy my
platter when they are connected "correctly"?
Maybe the control finally
got a signal and decided to load them.
Does anyone understand what might have happened?
Simple the heads are designed to fly and have a shape suited for that.
Flip them over and they are wrong shape, they don't fly, they dig in....
oops!
Make sure the correct heads are in there correctly.
Allison
9:33 a.m.
Does anyone
understand what might have happened?
Simple the heads are designed to fly and have
a shape suited for that.
Flip them over and they are wrong shape, they don't fly, they dig in....
oops! 
9:37 a.m.
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,
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.
I am not sure why this caused a headcrash. It shouldn't have done.
-tony
9:46 a.m.
On Sun, Dec 17, 2017 at 5:04 PM, Aaron Jackson via
cctalk
<cctalk at classiccmp.org> wrote:
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?
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,
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.
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.
9:55 a.m.
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? 
10:06 a.m.
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Aaron
Jackson via cctalk
Sent: 17 December 2017 17:56
To: Aaron Jackson <aaron at aaronsplace.co.uk>; General Discussion: On-Topic
and Off-Topic Posts <cctalk at classiccmp.org>
Subject: Re: RL02 weirdness
I just checked and it looks like they are in correctly. The head for the
top-side
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? of the platter is labelled down, and the lower head is
facing up. The only
thing I changed is connecting up->up and down->down.
So, I'm not sure. I cleaned the packs well a while back - I'm just hoping
there
wasn't something left over which caused the
crash.
Thanks,
Aaron.
If these are the ones you got from may I may have put the leads back the
wrong way round. :-(
I suspect they have been bounced about so much in my car they may be out of
alignment.
I would see about checking the alignment before doing anything else...
Dave
10:13 a.m.
-----Original
Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Aaron
Jackson via cctalk
Sent: 17 December 2017 17:56
To: Aaron Jackson <aaron at aaronsplace.co.uk>; General Discussion: On-Topic
and Off-Topic Posts <cctalk at classiccmp.org>
Subject: Re: RL02 weirdness
I just checked and it looks like they are in correctly. The head for the
top-side
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? of the platter is labelled down, and the lower
head is facing up. The only
thing I changed is connecting up->up and down->down.
So, I'm not sure. I cleaned the packs well a while back - I'm just hoping
there
wasn't something left over which caused the
crash.
Thanks,
Aaron.
If these are the ones you got from may I may have put the leads back the
wrong way round. :-(
I suspect they have been bounced about so much in my car they may be out of
alignment.
I would see about checking the alignment before doing anything else...
Dave 
11:32 a.m.
On 12/17/17 9:04 AM, Aaron Jackson via cctalk wrote:
I unloaded very quickly but I think the damage is
done.
I KNOW the damage is done.
NEVER attempt to load a pack if you haven't inspected it AND the heads first.
Was this combination ever known to work?
You now need to throw that pack out, and thoroughly inspect and clean the heads
and any pack to attempt to use in the future.
You also need to inspect the filter, purge the air filtration system if you haven't
done that already
along with cleaning the filtered air path in the drive
and run the spindle for a while before attempting to load the heads again.
Why would the heads be installed this way? and why did
it destroy my
platter when they are connected "correctly"?
The only thing that comes to mind is the servo system is going to be extremely
confused with the embedded servo information coming in the reverse direction.
11:46 a.m.
On 12/17/17 9:04 AM, Aaron Jackson via cctalk wrote:
The pack was cleaned with lint-free kimwipes and 99.9% isopropyl alcohol
not too long ago.
I unloaded very quickly but I think the damage is
done.
I KNOW the damage is done.
NEVER attempt to load a pack if you haven't inspected it AND the heads
first. Was this combination ever known to work?
The heads had loaded many times (with this pack) without crashing before
I connected the heads to the correct headers on the R/W module
(i.e. up->up and down->down).
You now need to throw that pack out, and thoroughly
inspect and clean the heads
and any pack to attempt to use in the future.
You also need to inspect the filter, purge the air filtration system if you haven't
done that already
along with cleaning the filtered air path in the drive
and run the spindle for a while before attempting to load the heads again.
I will check these things, thanks. The absolute filter is basically
brand new by the looks of it.
Why would the
heads be installed this way? and why did it destroy my
platter when they are connected "correctly"?
The only thing that comes to mind is the servo system is going to be extremely
confused with the embedded servo information coming in the reverse direction. 
2344
days inactive
2344
days old
9 comments
5 participants
participants (5)
-
aaron＠aaronsplace.co.uk -
aek＠bitsavers.org -
allisonportable＠gmail.com -
ard.p850ug1＠gmail.com -
dave.g4ugm＠gmail.com