PDP-11/35 Restoration

[cosam]

Earlier this year, I moved the PDP-11/35 which had been lurking in my basement to some spare space at my employer's offices. The last few weeks some colleagues and I have been working on getting the old girl working again. Our first evening was taken up by the usual cleaning duties and racking all the kit on the proper rails (some of which needed modifying) to make it easier to work on. After that we tested the processor and fitted some extra modules: a KW11-L clock interrupt, which works, and a KE11-E to provide the extra EIS instructions, which needs work. Last week we worked on the two RK05 disk drives, which show signs of life but need replacement bulbs (or probably LEDs) for their positioner transducers. Some of the guys took a bunch of photos and even a video or two, some of which are online here.

The company has a lot of Unix guys, so we're hoping to get at least 5th edition running, maybe a BSD if we can get hold of some bigger disks (maybe even Massbus as we have a TE16 tape drive and RH11 controller waiting for it). When we've got something worth showing, we'll give a proper demo which we can hopefully video and put online. Others are even already busy working out how we can make the system available over the Internet!

Cheers,

 

[Lou - N2MIY]

Steve,

Everything looks really beautifully clean! This machine will be a pleasure to work on. I am sure that you won't have much trouble getting the RK05s going either. The TE16 may be a bit of work, since there are many rubber items that tend to dry out. David of pdp8.net restored a TU10 and may have some tips for you.

Congratulations on your work so far.... We look forward to seeing those demo videos of the entire system in operation!

Lou

 

[tradde]

Steve,

Everything looks really beautifully clean! This machine will be a pleasure to work on. I am sure that you won't have much trouble getting the RK05s going either. The TE16 may be a bit of work, since there are many rubber items that tend to dry out. David of pdp8.net restored a TU10 and may have some tips for you.

Congratulations on your work so far.... We look forward to seeing those demo videos of the entire system in operation!

Lou

This make me dream of having a pdp-11/70 someday.

 

[RSX11M+]

This make me dream of having a pdp-11/70 someday.

I have that one every night.

 

[tradde]

Every night?

 

[cosam]

Everything looks really beautifully clean! This machine will be a pleasure to work on. I am sure that you won't have much trouble getting the RK05s going either.

The processor box and drives have been well looked after. They were in fact in production use until 2008 and some parts are labelled as being replaced as recently as 2006.

The TE16 may be a bit of work, since there are many rubber items that tend to dry out. David of pdp8.net restored a TU10 and may have some tips for you.

Yeah, we've not really looked at that in detail and unlike the other stuff its history is unknown. Apart from the rubber parts all the foam is shot (as usual) and I think it'd be a good plan to check those beer-can-sized electrolytics before powering up!

 

[Lou - N2MIY]

You 11/70 dreamer guys need to lower your standards. Either that or, if you can't be with the one you love, love the one you're with.

(Coming from the guy with the 11/04....)

Lou

 

[RSX11M+]

Represented in the DEC collection are 11/730, 11/34s, 11/23s, 11/73s, and several T-11s [Falcon being the largest]. Had an 11/04 and lost it [divorce] but it wasn't that great anyhow. So from here, exactly where you suggest I go?

11/70 sounds just right to me.

 

[tradde]

I'd be happy with any blinkenlight 11. All I have left now is my 11/84 which is nice, but has only a LED on the front.
Kind of boring if you ask me.

 

[pontus]

Very nice looking specimen! I also like the small raised floor. I thinking of doing something like that at home.

I personally rather have an 11/35 than an 11/70. Same look, close to the same capabilities but smaller form factor.

 

[RSX11M+]

It's the three phase power that worries me about the 70. My electric bill is high enough!

What am I worried about?? It's never gonna happen anyway. - DUH!

 

[tradde]

It's the three phase power that worries me about the 70. My electric bill is high enough!

What am I worried about?? It's never gonna happen anyway. - DUH!

Is it really 3 phase? That would be a problem.

 

[RSX11M+]

Yeah... if it's in it's original configuration. I've heard someone did a modification, but it had to be a whopper. I've got the system schematics here... I can look to see if it's really feasible to changeover. I'd bet it would be simpler to change out the supplies altogether for modern types. DEC's not been known for efficient ones on it's bigger machines. The PDP-10's were legendary bad. Compuserve redesigned them entirely. [supplies that is]

Then again, I'll worry about it when it's an issue.

 

[NeXT]

Ya' gotta make a sacrifice.
Speed but no console, or a console but slow speeds.

 

[RSX11M+]

11/70 ain't slow.

 

[jackrubin]

I've just received the boards for a sister machine (11/35) from Ed Groenenberg; now I'm hoping to convert a spare BA-11 into a machine as nice looking as yours. Great work - thanks for the inspiration!

 

[marmotking]

I have an 11/70...and an 11/45. I'm trying to make room in my basement to set them up and try to restore them. They're in unknown condition at the moment and not nearly as clean as the 11/35 shown here. What a gem!!! Currently, though, I dream of getting my VAX 11/750 up and running.

 

[RSX11M+]

I have an 11/70...and an 11/45. I'm trying to make room in my basement to set them up and try to restore them. They're in unknown condition at the moment and not nearly as clean as the 11/35 shown here. What a gem!!! Currently, though, I dream of getting my VAX 11/750 up and running.

ha: I am Green with envy!