Assuming I read you correctly, the mobo appears to have problems.
You should invest in a multimeter. 20$ or so from Radio Shack or even Walmart (probably in the automotive section). This way you can measure the voltages coming off the p/s pins accurately. Yes you sometimes need to "load down" a p/s to determine if it is functioning properly (in other words apply an actual resistance - the circuit it was meant to power or something equivalent. You can plug it into the mobo and test it by say pushing a paper clip into the back of the p/s connector for instance.
Sounds like your mobo has issues. You want to start playing with old PCs and stuff - find some replacement mobos and whatnot. I'm too disorganized at the moment to even offer to provide one. Others in the group (MARCH) are bound to. Try Bill Degnan. But he's hours away...
Besides swapping boards, try removing the socketed chips (CPU, etc.) and replacing just those. Or using that CPU in another computer or board. You have to have something else that runs an 8088 by now, don't you...
Regards and best of luck.
P.S - get a copy of "Inside the IBM PC", Peter Norton. Has to be PC-era. Has a picture of a mobo on the cover, but is very green. The earliest addition is not as useful as the slightly larger more commonly known one (i used to have the *newer* one, but have only the older, uglier, less useful addition now. Somewhere). It's a M-U-S-T if you're going to develop a basic understanding of what's going on under duh hood. You need to get a copy.
--- On Mon, 7/27/09, Joe Giliberti <starbase89 at gmail.com> wrote:
> From: Joe Giliberti <starbase89 at gmail.com>
> Subject: Problems with IBM 5150 Power
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
> Date: Monday, July 27, 2009, 7:03 PM
> I recently acquired a 5150. It is a
> 16-64k with two drives and color. I have
> not been able to boot it up yet. I cleaned the inside, and
> made sure
> everything was well connected. When I flick the power on,
> the CPU fan goes,
> and nothing else. There is power coming out of the
> motherboard and drive
> connectors, but there is nothing at the ISA slot. No beeps
> or anything. I
> tested the power supply with a modern CD drive. It worked.
> I removed the
> motherboard and inspected it for obviously bad components
> and scorch marks.
> I then opened the power supply. It was pretty clean, except
> for the hornet's
> nest inside. I haven't yet removed that board, but plan to
> soon. The fuse is
> intact.
>
> Can anyone suggest what to do next? I have PDFs of the
> Hardware Maintaince
> manual and the technical service manual.
>
> Thanks
> Joe
>
Back in December I posted about an open source, stand alone ASCII terminal
project for old computers -
http://www.classiccmp.org/pipermail/cctalk/2008-December/265312.html
The VT6, a simplified single host port version, is available now - PC
boards, partial kits and full kits of all parts. It was actually available
back in March, but the first run of parts sold out just on the Spare Time
Gizmos group and I never got a chance to announce it elsewhere. The second,
much larger, run of parts is now available and hopefully there should be
plenty this time around.
The VT6 is a small PC board, about 2.5" by 4", that uses a VGA monitor and
a PS/2 keyboard and is able to do pretty much anything a VT220 can. The
firmware is about 95% written in C (with about 5% assembler) and is open
source and GPL licensed. The tool chain used for development, including the
SDCC C compiler, is all free. The microprocessor is flash based and
firmware updates can be downloaded from any PC over an ordinary serial port.
If you need a terminal, it's just the thing to stick in the back of your
classic computer.
The hardware for the other version of this terminal, known as the VT5 is
also finished and really only needs the firmware to be ready. The VT5
supports multiple host ports and sessions with split screen displays,
downloadable fonts and (if we can get the firmware written!) ReGIS and/or
Tek 4010 type graphics.
The firmware is really the limiting factor for everything (isn't that
always the truth??) and we could use help with the programming. There's a
Source Forge project for the firmware here -
http://vt4.sourceforge.net
and the Spare Time Gizmos page for the VT6 parts and PCBs is here -
http://www.sparetimegizmos.com/Hardware/VT.htm
There's also a manual (unfinished - we could use help with that too!) -
http://www.sparetimegizmos.com/Downloads/vt.pdf
Bob Armstrong
Hi guys,
I seem to recall there being a few folks here with copies of old
Philips Semiconductor, Signetics and Mullard databooks kicking around...
Basically, I've dug my old Ground Control UTA-1 "Universal Teletext
Adapter" out of the cupboard, and I'd rather like to make it work on my
Linux box. I've found some details on the CITAC chip that controls the
tuning, and a bit more info on the tuner module, so at this point I can
connect it up, get an I2C ACK from the CITAC, and tune in a channel.
Problem is, my datasheet for the SAA5240A Teletext controller chip is
either an early release, or is just plain incomplete. For a start,
there's a reference to Ghost Rows Mode, which from what I can tell
allows access to the "extended" Teletext data rows which carry the
Fastext page-jumping data.
Does anyone have a copy of the "SAA5240 user's manual" to hand?
FWIW, I suspect the SAA5243 manual would be just as good, the register
maps seem to be mostly identical...
Thanks.
--
Phil.
philpem at philpem.me.uk
http://www.philpem.me.uk/
(This is a repost; my first attempt seems to have vanished into the aether)
Hi guys,
Apologies for the slight OT-ness of this post, but I seem to recall
there being a few folks here with copies of old Philips Semiconductor,
Signetics and Mullard databooks kicking around...
Basically, I've dug my old Ground Control UTA-1 "Universal Teletext
Adapter" out of the cupboard, and I'd rather like to make it work on my
Linux box. I've found some details on the CITAC chip that controls the
tuning, and a bit more info on the tuner module, so at this point I can
connect it up, get an I2C ACK from the CITAC, and tune in a channel.
Problem is, my datasheet for the SAA5240A Teletext controller chip is
either an early release, or is just plain incomplete. For a start,
there's a reference to Ghost Rows Mode, which from what I can tell
allows access to the "extended" Teletext data rows which carry the
Fastext page-jumping data.
Does anyone have a copy of the Philips/Signetics/Mullard "SAA5240
User's Manual" to hand? If so, I could do with scans or photocopies of
parts of it, especially the stuff about Ghost Row mode. I'm also open to
buying the book outright if anyone wants to get rid of theirs...
FWIW, I suspect the SAA5243 or SAA5246 manual would be just as good, the
register maps seem to be more or less identical (based on the
datasheets). Hardly surprising, really.
Thanks.
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
> Date: Tue, 28 Jul 2009 00:33:42 -0700 (PDT)
> From: William Maddox <wmaddox at pacbell.net>
>
> Ebay Item # 350229860975
>
> VINTAGE ANDROMEDA SYSTEMS 11/B ASI TAPE/DISK DRIVE
>
> Despite the seller's description, this looks to be a complete
> computer. Any idea what it is?
I don't know, but if you hurt your back lifting it, you'll have the
Andromeda Strain....
Jeff Walther
Looking for some UNIBUS size PCB mailing boxes. Sending
various spare boards out to people and have run out of
mailing boxes that are suitable. UK if possible. Mail me
of list if you have anything.
Thanks!
Ian.
On the surface, it's an auction for a Kenbak-1.
In reality it's the "CTI" version. But moreso, the seller is auctioning
"full rights" to the current owner's autobiography .... !? That is very
strange.
Suppose someone wants to write a book disparaging this man.
http://cgi.ebay.com/KENBAK-1-Vintage-PC-with-Books-Schematics-Much-More_W0Q…
--- On Thu, 7/30/09, Evan Koblentz <evan at snarc.net> wrote:
> In reality it's the "CTI" version.? But moreso, the
> seller is auctioning "full rights" to the current owner's
> autobiography .... !?? That is very strange.
>
> Suppose someone wants to write a book disparaging this
> man.
I believe Mr. Nielson has already written an autobiography
(indeed, an *auto*biography is, by definition, written by
its subject), and is acutioning the rights to publish it.
--Bill
Hi all,
On 30 July 1969 IBM announced the IBM System/3 in the United States.
It is today fourty year ago that IBM offered the first medium-sized
computer for the small business companies.
The System/3 was not compatible with the System/360, as it featured
a complete new architecture. It also featured a complete new
punch card format, which was a small revolution within IBM.
See for the development story behind the System/3:
http://www.ibmsystem3.nl/hist.html
IBM promoted this new system with a 14 minute promotion movie.
This movie can be seen on youtube.
Be patient, it takes until 3:22 until you find out what
it's about:
"Are you getting the most out of your workforce and tools?"
And until 8:18 before you see the new S/3.
See: http://www.youtube.com/watch?v=vRS3eXQ9gGY
and http://www.youtube.com/watch?v=S3Jrn9yNZAM
During its live span approx 50,000 System/3 where build.
Today only a few have escaped the scrapyard.
The number of still running S/3 can be counted on one hand.
See: http://www.ibmsystem3.nl/remaining.html
After the succesful S/3 IBM announced the S/32, S/34, S/36, S/38 and AS/400.
The S/38 was architecturally completely new compared to the S/3/32/34/36
All System/3 models had been withdrawn from marketing by June 1985.
--//--