RE: Nova 3 front panel

[Henk Gooijen]

Van: jim stephens

Re: MM11-L / G231 repair advice?

[Brent Hilpert]

On 2016-Jul-23, at 12:16 PM, Mattis Lind wrote:
> So after replacing a microcode PROM on the PDP-11/05 control board and then
> concluding that the remaining problem relating to indexed addressing was
> caused by one single micro code line that got missing when typed in,
> desoldering the PROM, program two more bits (0xf to 0x5), the CPU is now
> working. Passing the D0OA diagnostics and the D0NB (except for the mov r0,
> (r0)+ tests)
> 
> But during the journey the core memory died. I am used to things failing in
> my face. The M9301 board started of working. Then it developed some kind of
> amnesia, permanently forgetting what was once stored. When this was cured
> with yet another PROM, one, then a second DEC8881 driver on the M9301-YF
> gave up. But now it seems to work.
> 
> So finally I am back to the core memory. Luckily I had a spare set so I
> could find at least what board that was failing. Card swapping gave that
> the G231 module was at fault. The failure mode is that it does read out the
> contents once. The second time it reads out all zeros. Write never works.
> 
> Apparently it is the write / write back mechanism that is failing
> completely in the G231 module. Since it is in fact reading, the X / Y
> selection seems to work and most of the writing takes place on the G110 as
> far as I understand since it contains the Inhibit drivers. So what part of
> the G231 is specific for the write?
> 
> I have a few other G110 / G231 modules with different types of failure
> modes so it would be really nice if someone with MM11-L know-how would step
> forward and share all the details on this board set.
> 
> I will continue to browse the schematic and the user manual to try to find
> the failing component, but help is highly appreciated!

Speaking generally, without specific familiarity with these dec modules . . 

Writing is performed by driving the X/Y lines in the opposite polarity (current 
direction) than for reading.

Have you checked whether it affects the entire memory module or some block or 
selection of addresses within the module?

If it's a limited set of addresses it may just be an X/Y driver transistor for 
the polarity appropriate to writing.

If it's the entire module, you might look at how the drive polarity selection 
is done for the X/Y drivers,
somewhere it should trace back to the R/W/restore state sequencing for a memory 
cycle.
The problem may then be in that polarity selection or the state sequencing.

The inhibit circuitry does just that: inhibits writing (inhibits setting the 
cores to the 'set' or 'written' state),
so it doesn't sound as much like an inhibit issue, unless it's something like 
the inhibits always being enabled.

Re: heap of floppy disks

[Chuck Guzis]

On 07/23/2016 01:04 PM, Jay West wrote:
> I emailed privately... but I do have original pcplus 242, and pcplus
> 2.1 for win, and all the Borland packages.

Isn't at least some of this archived in the SIMTEL20 set?

--Chuck

Re: Multiflow Trace 14/300 close to being scrapped in Texas

[James Vess]

Awesome news! I'm happy it's going somewhere to be cared for or at least
stored.

Seeing systems like this get scrapped hurts my heart, losing history that
is there and still alive ( reasonably anyway ) is a shame. I'm just happy
that it will live to blink another day ;)

On Saturday, July 23, 2016, Evan Linwood  wrote:

> Hi Mark, it wasn't myself either.
> Apologies (and to Brian, James and Jon) I was watching & wanting to respond
> but got hit by a wall of things, then noticed that someone had bid on it.
> Very glad to see it was acquired, and that Chris could confirm.
>
>
>

RE: heap of floppy disks

[Jay West]

I emailed privately... but I do have original pcplus 242, and pcplus 2.1 for 
win, and all the Borland packages.

Re: Nova 3 front panel

[Vincent Slyngstad]

From: jim stephens: Saturday, July 23, 2016 11:41 AM
I was looking at this sale on ebay from Vince's part number.  Also it is a US 
shipping source, so may not save Henk anything.  But it is the lowest cost I 
found around.


10-PACK-Bulb-for-MINIATURE-LAMP-2187D-LAMP-28VOLTS-1-12WATTS

http://www.ebay.com/itm/152150229625


That price of $2+ per bulb is high, but the bulbs used to retail for
prices like that.  They were scarce, being replaced by LEDs or whatever,
and they just weren't making them anymore.

The Mouser prices and inventory seem to indicate that this has changed,
unless Mouser just has them on clearance or something.  (Maybe 28V
happens to still have demand?)

The Mouser sale for the CM2187 (think that may be the above ebay part) shows 
it a 28v lamp, 44 cents, and 3000+ in stock.


The CM2185 has a longer life (but half as bright) and is $0.35 qty 1.  Qty 10 is
more likely, so $0.32 vs .40 for the CM2187.  Either way it is pretty 
reasonable.


Not sure why the ebay sale is for so much, but Mouser looks like the place to 
buy if there isn't a minimum order amount or bad shipping / service fee costs 
from Mouser.


Agreed.  Shipping is probably $6 to $12 in the USA, and I don't see any
a minimum order.

   Vince 

Re: heap of floppy disks

[devin davison]

Unfourtunately alot of the sun and os/2 stuff from the larger crate seems
to be incomplete. Less than half of the numbered disks for each set. Next
to useless in my eyes. All of the software from the first crate is
complete, i can get to listing what is there tonight.

I am making images of the disks. They will be available on my server, and
ill put them up on bitsavers or something of the like.

--Devin

On Sat, Jul 23, 2016 at 3:19 PM, devin davison  wrote:

> I indeed do have procomm plus. disks 1 and 2. Let me see if they can be
> read.
>
> On Fri, Jul 22, 2016 at 8:04 PM, Tothwolf  wrote:
>
>> On Fri, 22 Jul 2016, devin davison wrote:
>>
>> I picked up two crates jam packed full of floppys today. Bunch of random
>>> old utilities in there, borland turbo asm, turbo pascal, windows for
>>> workgroups etc.
>>>
>>> I found a set of disks with the DEC digital logo on them. 4-5 disks,
>>> says dos for the dec pc. Some utilitys too. Are these of any use to anyone,
>>> or is it just a stock dos install with a dec sticker on the disk?
>>>
>>> There are little heaps of disks on just about every surface around here,
>>> i will post back with a complete list of what is here to see if anyone is
>>> interested in what is here. I just want some of the software off of the
>>> disks, i don't necessarily want to keep the two full crates of disks around
>>> . There is also an original copy of doom on floppy that looks to be
>>> complete.
>>>
>>
>> I'm still on the lookout for Procomm Plus for Windows (ver 2.11) if you
>> happen across that on 3.5" disks. I bought what was supposed to be a boxed
>> copy off eBay years ago and it was mostly complete... box, manuals,
>> license, but no disks :)
>>
>
>

Re: heap of floppy disks

[devin davison]

I indeed do have procomm plus. disks 1 and 2. Let me see if they can be
read.

On Fri, Jul 22, 2016 at 8:04 PM, Tothwolf  wrote:

> On Fri, 22 Jul 2016, devin davison wrote:
>
> I picked up two crates jam packed full of floppys today. Bunch of random
>> old utilities in there, borland turbo asm, turbo pascal, windows for
>> workgroups etc.
>>
>> I found a set of disks with the DEC digital logo on them. 4-5 disks, says
>> dos for the dec pc. Some utilitys too. Are these of any use to anyone, or
>> is it just a stock dos install with a dec sticker on the disk?
>>
>> There are little heaps of disks on just about every surface around here,
>> i will post back with a complete list of what is here to see if anyone is
>> interested in what is here. I just want some of the software off of the
>> disks, i don't necessarily want to keep the two full crates of disks around
>> . There is also an original copy of doom on floppy that looks to be
>> complete.
>>
>
> I'm still on the lookout for Procomm Plus for Windows (ver 2.11) if you
> happen across that on 3.5" disks. I bought what was supposed to be a boxed
> copy off eBay years ago and it was mostly complete... box, manuals,
> license, but no disks :)
>

Re: Nova 3 front panel

[Paul Koning]

> On Jul 23, 2016, at 2:41 PM, jim stephens  wrote:
> 
> 
> 
> On 7/23/2016 10:57 AM, Vincent Slyngstad wrote:
>> From: Henk Gooijen: Saturday, July 23, 2016 10:36 AM
>>> Somebody knows of a source for 28V 40 mA “grain” bulbs with wires?
>>> I could use some 10 … and 20 as spare 
>> 
> 
> The Mouser sale for the CM2187 (think that may be the above ebay part) shows 
> it a 28v lamp, 44 cents, and 3000+ in stock.   Not sure why the ebay sale is 
> for so much, but Mouser looks like the place to buy if there isn't a minimum 
> order amount or bad shipping / service fee costs from Mouser.

Mouser and its competitor Digikey are both large and well established 
electronic parts distributors.  They may have a minimum order, or a service 
charge for very small orders, but if so it's probably something modest like 
$25.  And you can go to them for pretty much every electronic part you might 
ever want, at least if it's current production.  I'm not sure about tubes, but 
apart from that...  I've used them both, Digikey more often.  Excellent outfits.

28V lightbulbs should be readily available, after all 28V is standard DC power 
in airplanes.

paul

RE: Nova 3 front panel

[Henk Gooijen]

Van: jim stephens

MM11-L / G231 repair advice?

[Mattis Lind]

So after replacing a microcode PROM on the PDP-11/05 control board and then
concluding that the remaining problem relating to indexed addressing was
caused by one single micro code line that got missing when typed in,
desoldering the PROM, program two more bits (0xf to 0x5), the CPU is now
working. Passing the D0OA diagnostics and the D0NB (except for the mov r0,
(r0)+ tests)

But during the journey the core memory died. I am used to things failing in
my face. The M9301 board started of working. Then it developed some kind of
amnesia, permanently forgetting what was once stored. When this was cured
with yet another PROM, one, then a second DEC8881 driver on the M9301-YF
gave up. But now it seems to work.

So finally I am back to the core memory. Luckily I had a spare set so I
could find at least what board that was failing. Card swapping gave that
the G231 module was at fault. The failure mode is that it does read out the
contents once. The second time it reads out all zeros. Write never works.

Apparently it is the write / write back mechanism that is failing
completely in the G231 module. Since it is in fact reading, the X / Y
selection seems to work and most of the writing takes place on the G110 as
far as I understand since it contains the Inhibit drivers. So what part of
the G231 is specific for the write?

I have a few other G110 / G231 modules with different types of failure
modes so it would be really nice if someone with MM11-L know-how would step
forward and share all the details on this board set.

I will continue to browse the schematic and the user manual to try to find
the failing component, but help is highly appreciated!


/Mattis

Re: Nova 3 front panel

[jim stephens]

On 7/23/2016 10:57 AM, Vincent Slyngstad wrote:

From: Henk Gooijen: Saturday, July 23, 2016 10:36 AM

Somebody knows of a source for 28V 40 mA “grain” bulbs with wires?
I could use some 10 … and 20 as spare 


Mouser has 950 CM2185 bulbs in stock, which should work nicely.
The Netherlands version of the site has the same quantity.  Maybe
ships from the same warehouses?  (Part number 606-CM2185.)

   Vince


Vince, Henk,
I was looking at this sale on ebay from Vince's part number.  Also it is 
a US shipping source, so may not save Henk anything.  But it is the 
lowest cost I found around.


10-PACK-Bulb-for-MINIATURE-LAMP-2187D-LAMP-28VOLTS-1-12WATTS

http://www.ebay.com/itm/152150229625

The Mouser sale for the CM2187 (think that may be the above ebay part) 
shows it a 28v lamp, 44 cents, and 3000+ in stock.   Not sure why the 
ebay sale is for so much, but Mouser looks like the place to buy if 
there isn't a minimum order amount or bad shipping / service fee costs 
from Mouser.

thanks
Jim

Re: Nova 3 front panel

[Vincent Slyngstad]

From: Henk Gooijen: Saturday, July 23, 2016 10:36 AM

Somebody knows of a source for 28V 40 mA “grain” bulbs with wires?
I could use some 10 … and 20 as spare 


Mouser has 950 CM2185 bulbs in stock, which should work nicely.
The Netherlands version of the site has the same quantity.  Maybe
ships from the same warehouses?  (Part number 606-CM2185.)

   Vince 

Compucorop 122E - Manual

[Matthias Draeger]

Hello, just came across this site. I recently got a Compucorp 122E, but 
without any manual. I would like to use this calculator for tests in 
programming - does anyone have a manual/pdf?


Thanks,

Matthias


ps.: this mail is for the "list" - how can I have access to the list? 
How do I see a reply, in case there is one?


Tel.0049-6741-1720


http://m-draeger.com/

Matthias Draeger

Auf dem Haehnchen 32

56329 St. Goar/ Germany

Re: Possibly rarest Apple 1 ever for auction

[Corey Cohen]

> On Jul 23, 2016, at 10:20 AM, Tothwolf  wrote:
> 
>> On Sat, 23 Jul 2016, Corey Cohen wrote:
>> 
>> My guess is that is was a test board for Apple.  There are some weird mods 
>> to the ram timing with a variable cap and to the negative supply that looks 
>> like they were experiments to figure out the tolerances of the chips.  The 
>> board was wave soldered.  You can't fake that on an Apple-1 because of what 
>> happens to the back of the board by the regulators. [...]
> 
> If you mean the crinkle tin plate under the solder mask, that doesn't happen 
> due to wave soldering. The heavy tin plate was applied that way in a separate 
> process before the solder mask was applied to the board. It used to be common 
> to do that to all sorts of boards in the 1970s-1980s. With modern boards, is 
> much more common now to just leave exposed copper/gaps in the solder mask and 
> allow those areas to take up solder from the wave soldering (or reflow) 
> processes.

The crinkle is exaggerated by the heat from the wave soldering.  Your right 
doesn't happen in modern boards because of how the tin was applied.  

Mike Newton tried to reproduce the technique in China for his replicas.  After 
many failed/peeling attempts he came close but even when wave soldered, it 
doesn't match the 1970's effect exactly, though it does crinkle.  

The other thing with wave soldered boards is how the Vias get filled in.  They 
sorta pucker, it's hard to explain but easy to show.  You can fill the Vias by 
hand, but they don't look the same as a wave soldered board.  In experiments I 
have tried a lot of different ways to replicate it.  You can always tell the 
difference if you look under a loupe.  

Cheers,
Corey 

corey cohen
uǝɥoɔ ʎǝɹoɔ

Re: Possibly rarest Apple 1 ever for auction

[Tothwolf]

On Sat, 23 Jul 2016, Corey Cohen wrote:

My guess is that is was a test board for Apple.  There are some weird 
mods to the ram timing with a variable cap and to the negative supply 
that looks like they were experiments to figure out the tolerances of 
the chips.  The board was wave soldered.  You can't fake that on an 
Apple-1 because of what happens to the back of the board by the 
regulators. [...]


If you mean the crinkle tin plate under the solder mask, that doesn't 
happen due to wave soldering. The heavy tin plate was applied that way in 
a separate process before the solder mask was applied to the board. It 
used to be common to do that to all sorts of boards in the 1970s-1980s. 
With modern boards, is much more common now to just leave exposed 
copper/gaps in the solder mask and allow those areas to take up solder 
from the wave soldering (or reflow) processes.

VT420 schematics

[Lars Brinkhoff]

Hello,

Does anyone have schematics for the DEC VT420 terminal?

Thank you,
Lars Brinkhoff

Re: Possibly rarest Apple 1 ever for auction

[Corey Cohen]

My guess is that is was a test board for Apple.  There are some weird mods to 
the ram timing with a variable cap and to the negative supply that looks like 
they were experiments to figure out the tolerances of the chips.  The board was 
wave soldered.  You can't fake that on an Apple-1 because of what happens to 
the back of the board by the regulators.  I had conversations about this board 
with Woz and Daniel Kottke who along with Steve Jobs were the only ones who 
could have had access to the roms and would have known what the board was.  The 
PCB house workers wouldn't have cared or known what to do with it.  This is 
before anyone even knew the name Apple.  

Other than a single replacement IC.  All the chips and soldered components are 
correct for something put together before the byte shop order just different 
parts than the rest of the boards.   All the pre NTI boards are very consistent 
in parts just the edge connectors were installed backwards on some.  The NTI 
varied on the smaller electrolytic caps. 

There is only one other known but lost to time Apple-1 with the same decoupling 
caps (they are different than the NTI, though similar).  That board was the 
preproduction board used for the Apple-1 printed Advertisement.   That board 
also used the same RAM chips, which Apple did not use in the end when they 
shipped the Apple-1, they used the cheaper plastic ones.  

So lots of evidence this was not something where someone grabbed a PCB for an 
unknown computer company risking their job and built their own.  

Cheers,
Corey

corey cohen
uǝɥoɔ ʎǝɹoɔ

On Jul 23, 2016, at 8:55 AM, Noel Chiappa  wrote:

>> From: Corey Cohen
> 
>> It was not someone at the PCB manufacturer. They would not have had
>> access to the prom software.
> 
> So, do you have a theory about where this came from? (There is absolutely zero
> snark here, this is a serious question. It's quite a puzzle, and an
> interesting one.)
> 
> Maybe a collaboration between two people, one at Apple, one at the PCB house?
> 'Make two extra boards, and I'll trade you the PROMs for one of them.' Can't
> do it with just a person at the PCB house - as you point out, need the ROMs.
> But you'd think that if someone at Apple just pulled a board, that would be
> noticed (board count wrong).
> 
>Noel

Re: Possibly rarest Apple 1 ever for auction

[Noel Chiappa]

> From: Corey Cohen

> It was not someone at the PCB manufacturer. They would not have had
> access to the prom software. 

So, do you have a theory about where this came from? (There is absolutely zero
snark here, this is a serious question. It's quite a puzzle, and an
interesting one.)

Maybe a collaboration between two people, one at Apple, one at the PCB house?
'Make two extra boards, and I'll trade you the PROMs for one of them.' Can't
do it with just a person at the PCB house - as you point out, need the ROMs.
But you'd think that if someone at Apple just pulled a board, that would be
noticed (board count wrong).

Noel

Re: Multiflow Trace 14/300 close to being scrapped in Texas

[Evan Linwood]

Hi Mark, it wasn't myself either.
Apologies (and to Brian, James and Jon) I was watching & wanting to respond
but got hit by a wall of things, then noticed that someone had bid on it.
Very glad to see it was acquired, and that Chris could confirm.

RE: Flex Disc options for the HP 9825

[CuriousMarc]

Thanks, I didn't know, I grabbed the image. That offers a path if I can ever
get an 9885 and single sides 8" discs...
Marc

> -Original Message-
> From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Paul
> Berger
> On the hpmuseum.net page for the 98217A ROM here is an image of what is
> reputed to be an initialized diskette for use with 9825 and 98217A
> http://www.hpmuseum.net/display_item.php?hw=166. When I get my
> 9825T I will look into 9885 emulation, I don't think it will be too
difficult but
> you may still need a GPIO unless I build the whole thing onto a
> plug-in card I don't think the GPIO would be too difficult to clone.
> But ideally I would still like to get access to a 98228A ROM to dump and
clone
> it, even though it is bank switched it should still be possible.
> 
> Paul.