VAX-11/780 boot disk

From: Clint Wolff <vaxman_at_qwest.net>
Date: Wed Jan 24 20:07:47 2001

On Tue, 23 Jan 2001, Richard W. Schauer wrote:

>
> On Tue, 23 Jan 2001, Clint Wolff (VAX collector) wrote:
> > > refrigerator dolly and human power, except the RP06 and the 780 where we
> > > used a come-along and a lifting frame I made. Heavy!
> >
> > Cool... I'm planning on moving my '780 into the basement with the same
> > concept...
>
> Actually, it didn't work all that well. If I had to do it all over again,
> I'd seriously think about taking the machine to bits. Of course, if you
> have something you can fasten the come-along to, it's easier. My lifting
> frame was intended to distribute the lifting force laterally on the
> bottoms of the walls of the building. The other problem is that there
> isn't a good place to pull on the 780; I bent the frame rails somewhat on
> the right side. Also it is top-heavy- once when we had to back up a bit
> it wanted to flip itself over. It took some persuasion to keep it
> sliding.
>

Hmmm... I have a return air duct in line with staircase... The plan
is (was?) to chain a pulley to the floor joist inside the duct and
run the cable from the come-along through it and to a nylon tow strap
around the base of the VAX... I'll have to check where the center of
gravity is on the machine at the angle of the stairs, I might need to
raise the strap higher on the side of the machine (thus risking the
bends)...

> > I have at least one (in the machine), but it may be bad... I bought one
> > from ebay, but again, it may be bad... I need a quick way to hook an
> > 8" floppy up to a running computer to read it...
>
> Ebay is the last place I would have thought of, but I guess it figures,
> everything else is sold there.
>

This is the only time I've seen them listed, they are backup copies
of the console and a couple diagnostic disks...

> > My plan is to just set up a new 25V unregulated supply once I figure
> > out how much current it needs to supply...
>
> You could probably do one of two easy things: 1. Unhook two phases and
> only run off one. I don't know what the current draw is, but the
> transformer may be able to handle it. It goes to a 6-diode bridge
> rectifier anyway. 2. (Temporary) Skip the power controller altogether.
>

I don't think a single phase will rectify to anywhere near 25V dc...
Perhaps two phase (with the third left open) will work...

Another thought I had was to use a power controller from another
machine like a PDP-11... I'll have to check the current carrying
capabilities of them though... I've got four or five of the things
that someone dumped in my office one day ("Well, they say DEC
on them, and you collect DEC stuff") ("DEC COMPUTERS, stupid" under
my breath)...

> Richard Schauer
>
Received on Wed Jan 24 2001 - 20:07:47 GMT