CatChat: Digital PDP-11/40

ACMS Collection
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CatChat: Digital PDP-11/40

CatChat: Digital PDP-11/40
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Description:

Digital PDP-11/40 Minicomputer
System Serial seems to be # 5076 (TBC)
If so, this is one of the original models (serial #'s below 6000)
Unit is incomplete as it is missing disk or tape units

Do you have any additional information or resources about this item? Did you own one, work with one or have you repaired one? Please join the discussion about this item in the ACMS collection here on CatChat. Alternatively, you can view other items in our collection here.
Created by CatalogBot
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The 11/35 & 11/40 use the same CPU board set, memory, and I/O boards. The front panel on the 35 & 40 is the same except for the silk screening. All of the 35 & 40 documentation is on Bitsavers: Index of /pdf/dec/pdp11/1140. It uses Unibus for the I/O bus, so you can borrow controller boards from any Unibus machine.

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Hi Mike, Appreciate you adding this tidbit using the CatChat system, which is exactly what we would love to see from anyone who has any pertinent knowledge to assist both us and others.

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Hi!

I have a working PDP-11/40, a second processor board set (also working) and the relevant documentation for the system.

Your system is the newer variant. It has square cutouts for the LEDs (instead of round) and the newer power distribution. You might be able to spot the difference in this image.

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image1920×3412 539 KB

I am in NZ, but if the Museum wants assistants fixing it up, something could probably be worked out.

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Very nice RK05s - unfortunately none of our are up and running at the moment - leaky caps for sure, smell awful!

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One of mine is running but I think I will replace some of the caps. I have heard that there is a cap across the 5v rail that when it goes bad can do quite a bit of damage to the PSU.

If/when I get to it I shall put together a list of caps I used and where to get them.

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