TU56 field strip
JackRubin
really looked worse than it is. Strip-down wasn't too bad - hardest
part was releasing the Mate N'Lock connectors for the motor harnesses
deep inside the cabinet. Everything came apart easily and the motors
all turn freely so I'm pretty optimistic about getting it running. Now
for some serious cleaning. The caps are a bit too far gone for
reforming though ...
Biggest problem will be cosmetics - anybody have a nice faceplate or
clean box for the power supply? I'll repaint the chassis and front
panel but not sure what to do about the lettering.
Lots of photos here - http://tinyurl.com/tu56-jack
Jack
Mike Ross
wrote:
Ye Gods.
http://lh4.ggpht.com/_JqfMAz6Y_gM/StE88V3dXHI/AAAAAAAAAvI/OOEsqYMVN74/s640/TU56%20026.jpg
If you get THAT reading tapes again, please tell me how you did it!
WRT lettering, I'm facing similar problems restoring power supplies with
cosmetic corrosion issues. Does anyone know a quick and dirty way to print
replacements for the transfers (relating to voltages, adjustments etc.)
typically found on power supplies? They would need to be printed white text on
clear material, either sticky, or actual decal-type transfers which you soak in
water and apply to the item. Some kind of special clear film or transfer
material, and a white ink (is there such a thing?) in an inkjet printer?
The 8/e has several examples of the type of thing I mean on the PSU:
http://www.corestore.org/8e-4.jpg
Mike
--
http://www.corestore.org
'As I walk along these shores
I am the history within'
glen herrmannsfeldt
(snip)
> WRT lettering, I'm facing similar problems restoring power supplies with
> cosmetic corrosion issues. Does anyone know a quick and dirty way to print
> replacements for the transfers (relating to voltages, adjustments etc.)
> typically found on power supplies? They would need to be printed white text on
> clear material, either sticky, or actual decal-type transfers which you soak in
> water and apply to the item. Some kind of special clear film or transfer
> material, and a white ink (is there such a thing?) in an inkjet printer?
I recently saw inkjet transparent labels, made to stick onto
envelopes, especially colorful greeting card envelopes.
Otherwise, there used to be rub-on transfer letters that would
do what you want.
-- glen
Marc W. Howard
> I was given a "rough" TU56 and I�m in the process of restoring it. It
I'm jealous. I've been looking for a TU56 for years.
Of course yours looks like it was last used in a clown rodeo but
restoring it is half the fun.
Marc
dpi
> Biggest problem will be cosmetics - anybody have a nice faceplate or
> clean box for the power supply? I'll repaint the chassis and front
> panel but not sure what to do about the lettering.
That is quite a project. Those caps look hideous! None of the ones
in my straight 8 have leaked but the capacitance is down so I either
needed to replace them or use a modern switcher. I ended up putting
in a 600 watt -15V switcher which was a little more money but the
efficiency increase is dramatic.
As far as the lettering goes, I am sure they were originally
silkscreened. You could probably do it this way and it wouldn't be
too bad. Look into silkscreening. You can probably make a
transparency on your inkjet or laser printer and use that to make a
silkscreen mask. It might seem like overkill since you are only
planning on doing a one off but it might be the most expedient way to
manage it. I suppose if you have good hand eye coordination you could
simply get a very fine brush and a bottle of white enamel and hand
paint the lettering back on.
The paint on the glass front panel of my 8 was peeling off at the
edges where finger oils and perspiration were getting under it. I
repaired this by cleaning all the paint off back to the next color
with a razor blade, cleaning the glass with alcohol, and then painting
the large open area with hobby enamel. This worked well enough that
it is still ok even 25 years later. The enamel I used is a little
more opaque than the original.
Doug Ingraham
Rapid City, SD
Marc W. Howard
> I was given a "rough" TU56 and I�m in the process of restoring it. It
I was all depressed that the TU56/TC11/RK05/LA36 on eBay just sold for
$7500 on 12/6:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250539539168
Imagine my surprise when an identical group on machines appeared on
Craiglist in LA for only $2000 also on 12/6:
http://losangeles.craigslist.org/lgb/ele/1497481062.html
Gee, I wonder if he'll send me pictures if I ask nicely!
I guess CL fraud isn't just limited to pinball machines.
Marc
Rich Alderson
> I was all depressed that the TU56/TC11/RK05/LA36 on eBay just sold for
> $7500 on 12/6:
It went for $7600. That's important, because we had the $7500 bid.
--
Rich Alderson "You get what anybody gets. You get a lifetime."
ne...@alderson.users.panix.com --Death, of the Endless
Mike Ross
<foobar_ma...@ieee.org> wrote:
>JackRubin wrote:
>> I was given a "rough" TU56 and I�m in the process of restoring it. It
>> really looked worse than it is. Strip-down wasn't too bad - hardest
>> part was releasing the Mate N'Lock connectors for the motor harnesses
>> deep inside the cabinet. Everything came apart easily and the motors
>> all turn freely so I'm pretty optimistic about getting it running. Now
>> for some serious cleaning. The caps are a bit too far gone for
>> reforming though ...
>>
>> Biggest problem will be cosmetics - anybody have a nice faceplate or
>> clean box for the power supply? I'll repaint the chassis and front
>> panel but not sure what to do about the lettering.
>>
>> Lots of photos here - http://tinyurl.com/tu56-jack
>>
>> Jack
>
>I was all depressed that the TU56/TC11/RK05/LA36 on eBay just sold for
>$7500 on 12/6:
>
>http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250539539168
Fuck a duck. I need to revise my insurance... and give up ANY notion of
expanding my collection of DEC bits. Fortunately IBM gear seems more sensible
these days.
>Imagine my surprise when an identical group on machines appeared on
>Craiglist in LA for only $2000 also on 12/6:
>
>http://losangeles.craigslist.org/lgb/ele/1497481062.html
>
>Gee, I wonder if he'll send me pictures if I ask nicely!
hehehe
Thanks for the heads-up; I'm already having fun with this guy ;-)
Philipp Hachtmann
>>>> Everything came apart easily and the motors
>>> all turn freely so I'm pretty optimistic about getting it running.
I got one with motors stuck to water in the basement a few years ago. Running again after opening
the motors and moderate cleaning.
>>> The caps are a bit too far gone for
>>> reforming though ...
Hm. I have working TU56 with leaky motor caps - still running. I'd suggest not to care about motor
capacitors until the motors run badly. There's no risk in doing so.
>>> Lots of photos here - http://tinyurl.com/tu56-jack
Oh, the capacitors look really bad...
Philipp
--
---
http://www.hachti.de
http://pdp8.hachti.de
http://h316.hachti.de
Philipp Hachtmann
Rich Alderson wrote:
> "Marc W. Howard" <foobar_ma...@ieee.org> writes:
>
>> I was all depressed that the TU56/TC11/RK05/LA36 on eBay just sold for
>> $7500 on 12/6:
>
> It went for $7600. That's important, because we had the $7500 bid.
That's quite interesting.... There's nothing in that lot that I don't have at least twice... What
was the reason for that price? The TC11? I'm planning to give away a TC11 next week - for only a few
other parts. Perhaps I have a misconception of the TC11's value? Any offers?
Tim Radde
I expected this set of hardware to go for maybe $2500. Even that is
a bit much even if the TC11 is pretty rare. I never
expected it to hit $7600. Too bad I don't have a TC11. I wonder if a
TC08 would fetch close to that? :) I doubt it.
Tim Radde
Al Kossow
> I wonder if a
> TC08 would fetch close to that?
It would be significantly MORE, esp if it has the
blinkenlights panel.
Tim Radde
Of course it has the blinkenlights panel. That's one of the fun parts
of these older machines, lots and lots of lights.
Philipp Hachtmann
> It would be significantly MORE, esp if it has the
> blinkenlights panel.
I'm not sure....
But if someone wants to trade a TC08 against a TC11 - let me know. Talking about the complete TC08
with panel, of course...
Philipp Hachtmann
have.
I've been offered a VT11 vector graphics controller (plus some other stuff, but from "another
class") for trade against a TC11. Isn't that good? I was happy before - now I'm a bit confused...
Tim Radde
How many dectapes can a TD8e operate? I'd guess one at a time even if
you have 4 hooked up since
it's software based. That's the beauty of the TC01/TC08. You can
have all tape spinning at once up
to 8. But I have never seen a configuration with all 8. My old local
college (had 3 TU55s) hooked up
to a TC01 and it was fun to see all 3 moving.
I don't know much about a VT11. Since I am a pdp-8 person more than a
pdp-11 I would rather
see dectapes on the 8. Although the TC11 does look impressive for
flipchips.
Philipp Hachtmann
> How many dectapes can a TD8e operate?
One dual transport (i.e. full TU56). It also needs five G888 modules in the drive, making it a TU56M.
> I'd guess one at a time even if
> you have 4 hooked up since
> it's software based.
Wrong causality :-)
It supports one drive only because it provides only one select line. To support more drives, more
select lines are needed. And yes, everything has to be done in software. But besides that it can do
everything the "bigger" controllers can do.
The "original" TU56 setup uses several TU56 drives wired in parallel. There are 8 select lines. Each
drive can select one of those to "hear" to it. When a drive is selected, it connects its head to a
set of common data lines - via relays! So the G888 modules sit in the controller. The TU56 are
completely uninterested in the data. You could record music on it without any modifications.
The TD8E needs the G888 modules plugged into the TU56. That doesn't change anything except that the
new extra signals between the controller and the G888 modules are accessible at alternative pin
locations on the data cable. So the original bus structure stays intact.
This should enable you to attach several drives by putting G888 in the first one only and then add
other drives down the chain as usual. Somewhere in the manuals I've read that - they did not mention
for what purpose - in a multiple TU56M configuration only the first unit needs the G888s.
The second TD8E problem is that it generates only two select lines. But you can easily add four TD8E
controllers into one 8/E.
But you also can make your TD8E react on all four device codes. And add some hardware: One
transparent latch on the TD8E itself. It will keep two bits of the device address. The latch's
output then will be used as the two high order bits that go - together with the original 0-1-select
signal - to a 3-to-8 multiplexer on the paddle board that plugs into the TU56. All you have to do is
to add two ICs, add some little jumpers, cut very few traces - and your TD8E will behave like four.
I'll try this out when I have built up the stuff around me....
> But I have never seen a configuration with all 8. My old local
> college (had 3 TU55s) hooked up
> to a TC01 and it was fun to see all 3 moving.
Hm. I might have the resources...
> I don't know much about a VT11. Since I am a pdp-8 person more than a
> pdp-11 I would rather
> see dectapes on the 8. Although the TC11 does look impressive for
> flipchips.
VT11 is cool. But: Who has a TC08 to part with?
-- Philipp
Mike Ross
Robert Williams
>Hm. I have working TU56 with leaky motor caps - still running. I'd suggest not to care about motor
>capacitors until the motors run badly. There's no risk in doing so.
>
Yes, I agree. This is quite different to the issue of leaky
electrolytics in a power supply and so long as the motor runs there is
little risk in the caps. I'd be tempted to worry about them later (and
it wouldn't matter too much what you replace them with).
Rich Alderson
It matters to this extent, that the motor caps in a TU56 are non-polarized.
JackRubin
wrote:
> Robert Williams <robertw63athotmail.com> writes:
> > On Tue, 08 Dec 2009 16:13:24 +0100, Philipp Hachtmann wrote:
> >> Hm. I have working TU56 with leaky motor caps - still running. I'd suggest
> >> not to care about motor capacitors until the motors run badly. There's no
> >> risk in doing so.
> > Yes, I agree. This is quite different to the issue of leaky
> > electrolytics in a power supply and so long as the motor runs there is
> > little risk in the caps. I'd be tempted to worry about them later (and
> > it wouldn't matter too much what you replace them with).
>
> It matters to this extent, that the motor caps in a TU56 are non-polarized.
>
The caps were easy since Dave Gesswein still had a couple of spares.
The chassis is being refinished and I'm working with a local
exhibition display company to reproduce the front panel. I'm learning
a lot about cutting and and printing plastics from this exercise. The
front panel is polycarbonate (Lexan), not acrylic (Plexiglass) as I
first thought. The base sheet is clear with printing on both sides,
including a "translucent" layer over the indicator lights. Right now
the question is the best way to cut the material - most likely laser
but possibly water jet. The original looks to be routed with a fine
diameter cutter (indicated by tool marks and radiused corners). Be fun
to see a costed bill of materials for some of this stuff.
Jack