30 Aug
2016
30 Aug
'16
1:54 p.m.
Hello,
The same cabinet has a TK50 and I foolishly put a
cartridge into it and
now it won't come out. It is called being 'stuck'. How do proceed to
get this TK50 cartridge out?
Error 'stuck' means that the tape has been "glued" to the head because
of the effect
of the tape binder being converted to adhesive due to age and moisture.
You can remove the cartridge in this way:
- pull the drive out of the machine
- carefully unscrew the metal cover over the internal reel and the head to expose it
- slowly insert a paper sheet between the tape and the head, in the same direction of the
tape, to detach it without damage
- slowly rotate the front motor (from bottom side) in way to rewind all the tape from the
back reel to the cartridge reel
- detach the tape leader if necessary
- now keep the electromagnetic cartridge unlock mechanism pressed, and remove the
cartridge from the drive
A tape in this condition of striction is probably unusable anyway, unless you back it up a
little in an oven,
but even so it could be readable just for a couple of hours
Also, the TQK50 controller never saw the drive and I
was wondering if
the PROM's (after 30 years) on the board lose their data?
Well, I never seen an UV-EPROM loose it's data, unless the erase window cover is
missing and the memory exposed to the sun light.
Andrea
30 Aug
30 Aug
3:18 p.m.
On 8/30/2016 1:54 PM, shadoooo wrote:
A tape in this condition of striction is probably unusable anyway,
unless you back it up a little in an oven,
but even so it could be readable just for a couple of hours
I wonder if the header
could be cut off and used for the other guy's
thread, who has the broken leader. That wouldn't involve the magnetic
media being involved, and might fix his tape cartridge. I think someone
suggested sacrificing a cartridge, this would be better than a possibly
good one as a source for the leader.
thanks
jim
3:32 p.m.
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of jim
stephens
Sent: 30 August 2016 23:19
To: General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Subject: Re: BA123 Side panels and Stuck TK50
On 8/30/2016 1:54 PM, shadoooo wrote:
thread,
A tape in this condition of striction is probably unusable anyway,
unless you back it up a little in an oven, but even so it could be
readable just for a couple of hours
I wonder if the header could be cut off and
used for the other guy's who has the broken leader.
I think you are referring to me. The leader I was talking about was the one
*inside the drive* that hooks the tape in the cartridge. I may have used the
wrong term, if so sorry about that.
That wouldn't involve the magnetic media being
involved, and might fix his tape cartridge. I think someone suggested
sacrificing a cartridge, this would be better than a possibly good one as
a
source for the leader.
So sacrificing a cartridge wouldn't help in my case....
Regards
Rob
3:40 p.m.
On Tue, Aug 30, 2016 at 6:32 PM, Rob Jarratt
<robert.jarratt at ntlworld.com> wrote:
I think you are referring to me. The leader I was
talking about was the one
*inside the drive* that hooks the tape in the cartridge. I may have used the
wrong term, if so sorry about that.
I saw your posts and saw that you were referring to a torn barb, so I
read that as the part that does fail and was replaced from time to
time with a fresh spare.
So far, I don't think anyone has come up with a good repair or
replacement other than "use a new one"... I think it might be
possible, now, to inexpensively laser-cut one from a suitable material
- I was thinking PET film of the appropriate weight and stiffness.
Someone mentioned trying 35mm acetate unsuccessfully.
Step 1: CAD up a good leader...
Step 2: experiment with different materials...
Step 3: Profit!
-ethan
8:08 p.m.
I've bought a pile of drives recently, and may have one that you can
scavenge. However I think mine may be TK-70's though.
I got some make good items from one guy for a botched sale, will see if
it was a 50 since you probably have to stick with those.
thanks
jim
On 8/30/2016 3:32 PM, Rob Jarratt wrote:
I think you are referring to me. The leader I was
talking about was the one
*inside the drive* that hooks the tape in the cartridge. I may have used the
wrong term, if so sorry about that.
31 Aug
31 Aug
12:26 a.m.
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of jim
stephens
Sent: 31 August 2016 04:08
To: rob at jarratt.me.uk; General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Subject: Re: BA123 Side panels and Stuck TK50
I've bought a pile of drives recently, and may have one that you can
scavenge. However I think mine may be TK-70's though.
Actually mine was a TK70, I *think* the leader is the same in both drives in
any case. If you have a spare that would be nice, but I think I may have a
spare tucked away somewhere anyway. My query was really about whether it was
possible to repair the tear, because one for the tip is not completely torn
off.
Regards
Rob
12:40 a.m.
On 31/08/2016 08:26, "Rob Jarratt" <robert.jarratt at ntlworld.com>
wrote:
We never repaired them at work, not least because the official DEC
guidelines said not to. Spare parts were cheap so it was a quick fix to
remove the cartridge and replace the leader.
--
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of jim
stephens
Sent: 31 August 2016 04:08
To: rob at jarratt.me.uk; General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Subject: Re: BA123 Side panels and Stuck TK50
I've bought a pile of drives recently, and may have one that you can
scavenge. However I think mine may be TK-70's though.
Actually mine was a TK70, I *think* the leader is the same in both drives in
any case. If you have a spare that would be nice, but I think I may have a
spare tucked away somewhere anyway. My query was really about whether it was
possible to repair the tear, because one for the tip is not completely torn
off. 
8:10 a.m.
On 8/30/2016 4:54 PM, shadoooo wrote:
Hello,
I removed the drive from the MicroVax and took off the metal cover on
the TK50. There was about 1/2 inch of tape on the takeup reel and it
moved freely.
The documentation on bitsavers told me what I should have known in the
first place. The Green and Red lights indicate the health of the drive.
When the drive first powers on the red light should be on during a brief
diagnostic test, then the red light should go out and the green light
should come on indicating that the drive has passed internal tests and
is ready. My TK50 never lights the green light and before I cleaned it
out the red light would blink indicating an internal fault.
Geez I hate these things.
The Bitsavers doc had a section for bench service and interpreting error
codes, does anyone know how to get these codes? Is there a PDP11 or
VAX diagnostic that reports these codes? Can you get at them from ODT
or the VAX console?
I still would like to rewind the tape and remove the cartridge, but it
looks like a difficult task to rewind by hand.
The same cabinet has a TK50 and I foolishly put a
cartridge into it and
now it won't come out. It is called being 'stuck'. How do proceed to
get this TK50 cartridge out?
Error 'stuck' means that the tape has been "glued" to the head because
of the effect
of the tape binder being converted to adhesive due to age and moisture.
You can remove the cartridge in this way:
- pull the drive out of the machine
- carefully unscrew the metal cover over the internal reel and the
head to expose it
- slowly insert a paper sheet between the tape and the head, in the
same direction of the tape, to detach it without damage
- slowly rotate the front motor (from bottom side) in way to rewind
all the tape from the back reel to the cartridge reel
- detach the tape leader if necessary
- now keep the electromagnetic cartridge unlock mechanism pressed, and
remove the cartridge from the drive
A tape in this condition of striction is probably unusable anyway,
unless you back it up a little in an oven,
but even so it could be readable just for a couple of hours Also, the TQK50 controller never saw the drive
and I was wondering if
the PROM's (after 30 years) on the board lose their data?
Well, I never seen an UV-EPROM loose it's data, unless the erase
window cover is missing and the memory exposed to the sun light.
Andrea
2819
days inactive
2820
days old
7 comments
6 participants
participants (6)
-
dj.taylor4＠comcast.net -
ethan.dicks＠gmail.com -
jwsmail＠jwsss.com -
robert.jarratt＠ntlworld.com -
shadoooo＠gmail.com -
witchy＠binarydinosaurs.co.uk