PDP-8/E Powersupply (was: Re: DEC PC04/PR8E Question)

From: Zane H. Healy <healyzh_at_aracnet.com>
Date: Wed Nov 28 18:15:46 2001

> > OK, the last part of my shipment just showed up, the Papertape reader. I'd
> > thought the PC04 was a reader/punch. Am I correct in my revised
> > assumption, that it came in three models; reader/punch, reader, and punch?
>
> I've heard of punch/reader and reader-only models. Never heard of a
> punch-only one. It could exist, though.

I'm basing the guess about a Punch only model from the pictures of the
switches in the printset I've got. It shows four layouts; Reader, Punch,
and two types of Punch/Reader.

> Well, on the front there should be a switch panel with 2 swtiches on it
> (reader on/off and tape feed). The punch/reader version has 4 swtiches
> (The other 2 are the same 2 functions for the punch).

That much at least looks complete.

> Inside the punch takes up the right hand side of the chassis. The logic
> backplane and PSU are on the left (the backplane will be fairly empty for
> a reader-only version, I think). The reader sits in the middle -- it's
> very simple -- a stepper motor with a large sproket wheel on the shaft, a
> 'festoon' lamp, and a phototransistor array. And not a lot else.

Hmm, in this case it sounds like I might have a complete Reader if I'm
lucky. I've not really spent much time looking at it yet. So far I've
spent my time looking into the PDP-8/E. Overall it looks pretty good,
in part thanks to the fact that the previous owner had started to restore it
a couple years ago.

I'm getting ready to see about checking out the powersupply, hopefully
either tonite or tomorrow morning. Is it safe to power it on to test the
voltages without any kind of a load?

Also, is there anyway to 'lubricate' the switches on the front panel?

                        Zane
Received on Wed Nov 28 2001 - 18:15:46 GMT