Looking for an T5611-25 CRT (or -7 or -2)


Bob Rosenbloom
 

I know this is a long shot, but I'm looking for an T5611-25 CRT for use in restoring an DEC LINC-8 minicomputer.
It used a modified Tektronix 561B oscilloscope, with DEC plug-ins, and the P25 phosphor CRT with no graticule.
The one in the LINZ has a badly burned face. A P7 or even P2 phosphor would also work though would look
different than the original. So basically any slow phosphor and no graticule.

Some cell phone photos of the LINC and scope are on my web site here:
http://www.dvq.com/dec-linc8/


Keith
 

Hi Bob,

If you really need a 561b CRT, then the TEk part number you would seem to need is 154-0614-00

That’s external graticule, Standard p31 phosphor and Standard B14-38 basing.

Note that the -01, -02 and -03 versions of this 154-0614-xx part number are electrically and physically the same, except P2, P7, and P31 phosphors

Is your CRT ceramic? Can you accept a glass CRT?

If so, there is an electrically equivalent earlier CRT, in glass, the T5032. There are about eleven TEK T5032 part numbers that would appear to me at first glance to work, if the glass vs. ceramic thing doesn’t blow up your world.

See them, here: https://w140.com/tekwiki/wiki/T5032

The first eleven p/n have external graticule. Some phosphors are “better” for you than others.

I see at least one complete 561b on fleabay - being parted out. That’s here, and looks like it might be an external graticule CRT.

https://www.ebay.com/itm/192947024206?_trkparms=ispr%3D1&hash=item2cec89f14e:g:2G0AAOSwqrNgCbE1&amdata=enc%3AAQAGAAACkPYe5NmHp%252B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSd3M8ngECaRA0SmyU4KT%252FnoWoOfkiFaIW2SJ8lxc2ql%252Bb5XWyxfgDJaThucyAKkrugV0zON4FNfd7a6vwaJdBMsTZkoiO6Jh%252BlD8lWxl90KMRRKnk4jNtjM8BnNwk%252BQ8z9e0HakfOXn9jQ0JiF7vDVG7opKEeF%252B9efKKpTnfnEwIiBWStepSxEWv%252FuSo8zjqpQPOP%252FaiPxd%252Bvp3y4fSezT8OnjmYWzwfzqXgRHuWqb85h6FzSu5j%252FPPgFbIiq2MFCsHOW4y8YCmJyJJDWBfnpA1SyeuZFtmzLLuVsLStUfvwWEDg9RK%252FT1abwuCxYvr%252BzzCp6cfdWjMh1ph3dnAoJHMGljHdYfO4jjXqsXWHn3e78xK%252B2aPcS18m3Etv7YaQgkbgHej587Al7sJqV0gexCevefT2Rv3DG7VopNJqbaDLxLiLAyeuqFX40vbwwEB8ruYUhwfOwaKc%252FYJ2EMjwI7hQIPbP0NwRlbg9geHHe0mzd6%252FGaKz9gt4NYzPju9tkEU5J9MiAlp8uDRNuZpr2FC3AhzfCcM21HLaOMEmyxnqQSaC3Hf4tGD2SJLIEgJSnrZWTGU9ifzRfbO%252BOXohPymi%252ByJFbvWibs01vmF0od4HHmb6nEA%252B%252BmPEQ%252FRfWFQaKracYWfVBH9jCRL1Bc86%252Bm4T5iKMneKGHsHRBejgLV8XsyrGX0ov8p0tKVPOpxQcRXMWeAk1gdVVKNX7DdwrFM6eS%252BFjYJncYqIFgZTbxH%252Fj3IlRkP2oqyehJf58paouetUd1uCgeciNBQIqsd9ieegBQ7V9A1Oh%252FdT9gqJVk6YqPjp9a8dgeBtyeK7rWZM%252Bt3%7Campid%3APL_CLK%7Cclp%3A2334524

Hope this helps


Bob Rosenbloom
 

Thanks for all of the options, gives me a lot more part numbers to search for. It turns out my CRT is marked T5032-25 on the glass and T5611-25 on a label so I guess it could use either one.

Glass or ceramic is fine, I just need the slow phosphor and no graticule.

It's interesting that none of the part numbers show the P25 phosphor that's actually used in the scope I have. May have been a special order by DEC. A P7 would be the next best choice. I did buy a ceramic P2 phosphor CRT with graticule off of eBay just to have something to play with until I can find the more correct no graticule one.

Thanks!

Bob


stevenhorii
 

We had a PDP-12 in our lab years ago. We got it when another department was
discarding it and we adopted it. Ours had a different color scheme from the
LINC-8 systems, but it was the same machine. Ours had a A-D converter in
the rack above the scope - the same modified Tek scope that is in yours. We
played “Spacewar” on it (we did use it for some lab data acquistion work).
It had a pair of DECtape drives.

The engineer I shared the lab with left a couple of years before I did.
When I left, I left that PDP-12 behind along with Tek 585 and 547 (the one
scope I wish I had taken with me) scopes. I did take the 556 but it sat on
my bench at home unused. I sold it off at a hamfest (should have kept that
one, too). The PDP-12, a PDP-8 system (DF-32 disk, two DECtape drives, 8K
memory, high-speed paper tape reader and punch, plus the ubiquitous ASR-33
Teletype), and the Tek scopes were all offered to me. Since I didn’t take
it, it all went into storage in an area of the building that was slated for
then future development. When I visited a few years later, what had been
“shell” space had been fully developed. All that stuff got scrapped.

As I recall, that modified Tek scope in the PDP-12 had a separate
edge-lighted graticule. The plug-ins were the same in each plug-in bay and
were basically amplifiers to run the scope in XY mode.

Seeing the photos of the LINC-8 brought back memories of using those front
panel switches to key in the RIM loader so we could load the BIN loader
from the ASR-33 (slow and noisy). On the PDP-8, we still had to enter the
BIN loader, but could then load the RIM loader from the high speed reader.
If we were not doing a cold start, we could also start up from the DF32
disk or DECtape. I did use the Tek scopes for troubleshooting - usually the
Teletype and trying to look at the various timing signals in it or the
current loop interface when it wasn’t working right.

On Sun, Jul 11, 2021 at 23:02 Bob Rosenbloom <bobalan@sbcglobal.net> wrote:

I know this is a long shot, but I'm looking for an T5611-25 CRT for use in
restoring an DEC LINC-8 minicomputer.
It used a modified Tektronix 561B oscilloscope, with DEC plug-ins, and the
P25 phosphor CRT with no graticule.
The one in the LINZ has a badly burned face. A P7 or even P2 phosphor
would also work though would look
different than the original. So basically any slow phosphor and no
graticule.

Some cell phone photos of the LINC and scope are on my web site here:
http://www.dvq.com/dec-linc8/







Ulf Kylenfall
 

At the Onsala Space Observatory, we had a LINC8 too. I operated it in ~1975/1976
as it was in used for processing data from the 25M telescope on 4 GHz.
I recognized the upside-down R561. Remember loading the tapes and also
the procedure to manually starting the boot-loader. Bottom left beside
all the data switches, there was a knob "Chime". Turning it on, the processing
could be "heard". If the system hang, the character of the sound would change.

The LINC 8 was salvaged from being scrapped and is on display at
the observatory today.

Ulf Kylenfall SM6GXV
SR Research Engr (Retired)
ex Onsala Space Observatory


Bob Rosenbloom
 

I also have a PDP-12, though mine uses a DEC VR14 for the monitor. It's a 11 or 12" CRT with magnetic deflection and a P7 phosphor. It also has two TU-56 DECTAPE units but unfortunately no DF32 or paper tape reader/punch. A few photos of the PDP-12 are here:

http://www.dvq.com/dec-pdp12/

The VR14's tube was not lighting up so I removed it. Turns out the base was loose and actually fell off. Nothing was broken, the wire pins out of the back of the CRT just were not soldered to the base anymore. I re-soldered them and glued the base back on and now the tube lights up. There's still work need on the deflection amps though.

Here's a photo of my 12 bit DEC collection showing the LINC-8 next to the PDP-12. http://www.dvq.com/dec-pdp12/dec-12bitters.JPG

The PDP-12 is built out of M-series flip-chips where were TTL based. The LINC-8 uses mostly R series transistor, no IC, modules. It a few years older than the PDP-12. At the far right is a PDP-5 which used system building block modules. They were made out of germanium transistors. Same modules as used in the original LINC computer and DEC PDP-1.

There's two Tek 7954 scopes at the left, and an RM-503 above a PDP-8/i. That has a nice, bright, P2 phosphor CRT.

The LINC-8 is going to be a big project. It's missing around 100 cards for one, then the badly burned CRT, and it's missing it's LINCTAPE drive.


Tim Phillips
 

From Tim P (UK)

Awesome collection ! Is that a Calcomp Drafting Plotter partly cut off on
the far right-hand side of photo ?
I remember seeing one plotting layouts for IC fab, which were then
photo-reduced by many orders of magnitude using ultra-high-resolution
lenses by, I believe, N*k*n, to make the masks. (pre-EBL)
Also, some PDPs used the Tek storage monitors, I think the 604 and 611.

Tim

On Tue, 13 Jul 2021 at 04:27, Bob Rosenbloom <bobalan@sbcglobal.net> wrote:

I also have a PDP-12, though mine uses a DEC VR14 for the monitor. It's a
11 or 12" CRT with magnetic deflection and a P7 phosphor. It also has two
TU-56 DECTAPE units but unfortunately no DF32 or paper tape reader/punch. A
few photos of the PDP-12 are here:

http://www.dvq.com/dec-pdp12/

The VR14's tube was not lighting up so I removed it. Turns out the base
was loose and actually fell off. Nothing was broken, the wire pins out of
the back of the CRT just were not soldered to the base anymore. I
re-soldered them and glued the base back on and now the tube lights up.
There's still work need on the deflection amps though.

Here's a photo of my 12 bit DEC collection showing the LINC-8 next to the
PDP-12. http://www.dvq.com/dec-pdp12/dec-12bitters.JPG

The PDP-12 is built out of M-series flip-chips where were TTL based. The
LINC-8 uses mostly R series transistor, no IC, modules. It a few years
older than the PDP-12. At the far right is a PDP-5 which used system
building block modules. They were made out of germanium transistors. Same
modules as used in the original LINC computer and DEC PDP-1.

There's two Tek 7954 scopes at the left, and an RM-503 above a PDP-8/i.
That has a nice, bright, P2 phosphor CRT.

The LINC-8 is going to be a big project. It's missing around 100 cards for
one, then the badly burned CRT, and it's missing it's LINCTAPE drive.






 

The vintageTEK Museum can probably supply a CRT, but I doubt we have anything but P31 phosphor. I will be at the Museum tomorrow (Wednesday) and will check our stock.

--
Bob Haas


Bob Rosenbloom
 

Yes, that's a Calcomp 960 plotter with it's 907 controller. Some better photos of that can be seen about 1/3 the way down here: http://www.dvq.com/oldcomp/misc.htm. I restored that plotter about 10 years ago.

DEC used the 611 monitor on some of their PDP-8 systems. They painted it black and rebadged it DIGITAL. I have a few of those but they are not currently hooked up to anything. Fun stuff.


Bob Rosenbloom
 

Thanks for checking. I did notice on the DEC schematic for the LINC, they show it as a 561A scope and the phosphor to be a P19.