Julian asked:
> Okay, so I was thinking, would it be possible to replace the
regulators and
> whatnot in a BA11 with several standard PC power supplies? Obviously
there
> would be adjustments that need to be made, but considering the DEC
units are
> now 20+ years old and the out-of-service modules may have dried up
caps,
> would this not be a possible option?
"BA11" covers a lot of chassis/backplane combinations, both Q-bus and
Unibus and not really any bus. I suspect you're talking about the 10.5"
high Unibus box. Dried up caps in the modules are far from a fundamental
difficulty. Compare that with re-doing the power bussing on the
backplanes
and replacing a couple of caps seems downright easy :-).
Not all the backplane signals are drop-in compatible with PC-clone power
supplies, but when third-party manufacturers used PC-clone power
supplies
for Q-bus chassis the extra signals were easily generated with a little
board.
On the Unibus, you probably need at least a token 15V supply and maybe
one that can give substantial currents (depending on what boards you've
got.) Some of those will run off +12V just fine, but others won't
Look at Strobe Data's Unibus backplane for an example of one way to
approach the problem: http://www.strobedata.com/home/ubus.pdf
One warning: few "350W" PC clone power supplies are actually capable of
pumping out half that much power. There are good PC-clone supplies but
at
that price point the "industrial" switchers are not too far off in price
(and are
far more flexible in terms of configuration.)
Tim.
Got a box of SCSI drives a while back, and in there is one that's apparently
18G, but it's marked "LV-D" which from my understanding of things won't work
with anything I have here. Can any of you guys use this?
Ideal for me would be a trade for something roughly comparable in size...
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
Just got an email from Down Under from a fellow with one of these. Uses 2
3.5" single-sided drives in what he thinks is a 280KB format. His unit has
a dead keyboard.
Before I have him send me sample of the diskette, does anyone know anything
about these?
Thanks,
Chuck
That's what I figured, but I thought I'd check with people that had more
expert-ness than me :)
> -----Original Message-----
> From: cctalk-bounces at classiccmp.org
> [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Jay West
> Sent: Monday, March 27, 2006 11:15 AM
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: Curiosity about power supplies (BA11)
>
> I haven't checked the specs, but I'd be surprised if the
> standard PC supplies could put out the amps required.
>
> Jay
>
>
Okay, so I was thinking, would it be possible to replace the regulators
and whatnot in a BA11 with several standard PC power supplies?
Obviously there would be adjustments that need to be made, but
considering the DEC units are now 20+ years old and the out-of-service
modules may have dried up caps, would this not be a possible option?
I'm just curious, I'm no electrician, nor have I looked over the leads
yet.
Secondly, if I have less than half the BA11 box full of cards, do I need
both of the fans plugged in?
Julian
> I downloaded the TC11 and TC-131 manuals.
> TC11 has two 40-pin connectors
As I said, different manufacturers sold slightly different cabling.
The hex board is the basic controller for 800 bpi, you daisy chain
the read/write cable to the quad board if you needed 800/1600 support.
I've been contacted by someone in NJ with a couple of AT&T "EO"
handheld computers to dispose of ... Anyone on the list with an interest
in these that is located "close"? - If so, contact me and I'll pass on the
info.
Dave
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
http://www.parse.com/~ddunfield/museum/index.html
