Re: Looking for North star software

[allison via cctalk]

On 07/03/2018 01:58 PM, Fred Cisin via cctech wrote:
> On Tue, 3 Jul 2018, Stephen Pereira via cctech wrote:
>> I believe that Mike Douglas has a utility program that you can get
>> into a Northstar Horizon, and then it can receive a .DSK image sent
>> from the terminal and it will write the disk for you in the Horizon.
>> It’s called PCtoFlop and I think he has it in his archive here:
>> http://deramp.com/downloads/north_star/
>> 
>> Good luck!
>
> You "get it into a NorthStar", by already booting the NorthStar to
> CP/M, and using PIP.
>
> It looks like an excellent way to handle more images, including
> N*-DOS, AFTER you have CP/M working.
>
NO matter what first you have to boot the horizon and if you lack
prepared media its a hard stop.
Mike Douglass solved it by putting an Eprom on the ZPB-A as there is a
spot for a 2708 1K part.
He made up a header to use more common signal voltage parts like
2716/2732 and so on.
With a machine language monitor that allows loading bytes to memory the
process is then easy.

Me I cheated and used a spare 64K memory board that used 2kx8 parts and
put an eprom (2716) in
the F000H space.  Change the CPU boot address jumpers from E800/E900 to
F000h and now
you can talk to it via serial port.

The PCput and PCget are handy and no so big to hand insert.

Allison

Re: Looking for North star software

[Stephen Pereira via cctalk]

I believe that Mike Douglas has a utility program that you can get into a 
Northstar Horizon, and then it can receive a .DSK image sent from the terminal 
and it will write the disk for you in the Horizon.

It’s called PCtoFlop and I think he has it in his archive here:

http://deramp.com/downloads/north_star/ 


Good luck!

smp
- - -
Stephen Pereira
Bedford, NH  03110
KB1SXE


> --
> 
> Message: 14
> Date: Tue, 3 Jul 2018 00:16:45 +
> From: dwight 
> To: Fred Cisin , "General Discussion: On-Topic and
>   Off-Topic Posts" 
> Subject: Re: Looking for North star software
> Message-ID:
>   
> 
>   
> Content-Type: text/plain; charset="us-ascii"
> 
> I was thinking someone has already done this. If no, as you say, it is not an 
> impossible task.
> 
> The TSS/B is suppose to be their scientific package. It at least has BASIC in 
> it. I have another disk marked CP/M in the same box. I should be able to put 
> something together under CP/M.
> 
> It is a North Star Horizon. There seems to be some images out there so I 
> don't know how they are being captured.
> 
> Dwight
> 
> 

Re: Looking for North star software

[Fred Cisin via cctalk]

You "get it into a NorthStar", by already booting the NorthStar to
CP/M, and using PIP.


On Tue, 3 Jul 2018, allison via cctech wrote:

NO matter what first you have to boot the horizon and if you lack
prepared media its a hard stop.
Mike Douglass solved it by putting an Eprom on the ZPB-A as there is a
spot for a 2708 1K part.
He made up a header to use more common signal voltage parts like
2716/2732 and so on.
With a machine language monitor that allows loading bytes to memory the
process is then easy.
Me I cheated and used a spare 64K memory board that used 2kx8 parts and
put an eprom (2716) in
the F000H space.  Change the CPU boot address jumpers from E800/E900 to
F000h and now
you can talk to it via serial port.


Thanks

That answered several questions that I was wondering about!

--
Grumpy Ol' Fred ci...@xenosoft.com

Re: Looking for North star software

[Fred Cisin via cctalk]

On Tue, 3 Jul 2018, Stephen Pereira via cctech wrote:

I believe that Mike Douglas has a utility program that you can get into a 
Northstar Horizon, and then it can receive a .DSK image sent from the terminal 
and it will write the disk for you in the Horizon.
It’s called PCtoFlop and I think he has it in his archive here:
http://deramp.com/downloads/north_star/ 

Good luck!


You "get it into a NorthStar", by already booting the NorthStar to 
CP/M, and using PIP.


It looks like an excellent way to handle more images, including N*-DOS, 
AFTER you have CP/M working.

Re: Looking for North star software

[allison via cctalk]

On 07/02/2018 06:27 PM, Fred Cisin via cctech wrote:
> On Mon, 2 Jul 2018, dwight via cctalk wrote:
>> I have a machine that I'm just now bringing up. I have some boot
>> software but it is TSS/A that is the accounting multi-user package.
>> I'd really like the TSS/B floppies instead. I'd settle for images.
>
> Sounds like fun!
>
> What model Northstar?

There are three basic systems:
Horizon Single density
Horizon Double density same as single save for newer controller.
Advanatage, not s100!

>
> Once you get some images, have you worked out a way to get the images
> onto hard-sector disks?
>
If you can get code into the box NS dos can write disks from memory
images.  The based NS* horizon
roms are minimal and only boot a disk.  The easy path is if everything
works get a copy of NS* DOS
and boot it.  Then IO via serial gets easy.

> AFTER you boot the machine, with some minimal programs, you can
> transfer data into the machine through serial port.
Once NS*Dos or CP/M is there yes.  Until then the box is pretty useless.

Plan B is get or make a Eprom board with a monitor utility into the
h or FXXXh ram block (max 4K).

Plan B' get a cpu card with rom on it. 

NOTE: pins 20 and 70 are grounded so any card that uses those pins will
likely have to be modded.
(those are memory protect and unprotect for that era, IEEE 696
reassigned them).


Allison

Re: Looking for North star software

[dwight via cctalk]

I'm told that the N* controller can write H89 formated disk but the H89 
controller can't do N* format. I could have that backwards but that is what I 
recall. One can't do the other.

The H89 hard sectored controller is single density only, while the newer N* can 
do both single and double density, still hard sectored though. There is always 
confusion on the N* controllers as to which can do double density. My research 
indicates that the MDC-nA are single density only and the MDC-nDA can do both ( 
n is a rev. number 1, 2, 3, or 4).

Dwight




From: cctalk  on behalf of Fred Cisin via cctalk 

Sent: Tuesday, July 3, 2018 11:08:18 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Looking for North star software

On Tue, 3 Jul 2018, dwight via cctalk wrote:
> I'm not as worried about 10 hard secrtored disk. I still have the punch
> I had made for my H89. I can create 10 sector from old 360K disk.

If you have a working H89 (hard sectored), then you should be able to
write a program to run on the H89 to write hard sectored disk images!
Can it do single density 256 byte sectors?  or MFM 512 byte sectors?

.ASM for PCTOFLOP should be available, as a guide to what you need, but
will need modification for the H89 disk controller.

Most of the NorthStar disk images should be availablem once you've got the
H89 writing disks from them!

Once you've got the NorthStar booting CP/M plus a copy of PIP, you can
then continue on it.

Re: Looking for Tektronix 4051 or 4052 Display Board

[Pete Lancashire via cctalk]

Yes but they're in pretty bad shape the units are under a tarp in a Briar
Patch for about 2 years in the Pacific Northwest. Amazingly enough one of
the deflection boards had enough working parts the CPU board for the 4051
was so corroded the lids fell off the chips. I only kept them to offer the
CRTs.

On Tue, Jul 3, 2018, 2:25 PM Monty McGraw  wrote:

> Pete,
>
> Thanks for checking on the display board.
>
> Are any of the other boards, power supplies or keyboards left in the 4051
> or 4052?
>
> Monty
>
> On Tue, Jul 3, 2018 at 4:19 PM, Pete Lancashire via cctalk <
> cctalk@classiccmp.org> wrote:
>
>> -- Forwarded message -
>> From: Pete Lancashire 
>> Date: Tue, Jul 3, 2018, 2:18 PM
>> Subject: Re: Looking for Tektronix 4051 or 4052 Display Board
>> To: Monty McGraw 
>>
>>
>> Yeah the two display boards went to Europe.
>>
>> If anybody needs three perfectly good 11 inch CRTs, deflection yolks
>> excetera come to Portland Oregon and they're yours or have somebody pick
>> them up for you they're in the scrap pile and scrap is going in about a
>> month. Each CRT contains about $35 worth of gold.
>>
>> On Tue, Jul 3, 2018, 2:12 PM Monty McGraw  wrote:
>>
>> > Pete,
>> >
>> > I'm in Texas near Houston.
>> >
>> > The Display Board is the vertical board to the left of the CRT.  It has
>> > several cables at the bottom to pin headers and the cable to the neck of
>> > the CRT.
>> > It also has connectors to the power transistors that simply unplug when
>> > you remove the Display Board.
>> >
>> > Here is a picture of a display board:
>> >
>> https://drive.google.com/file/d/0Bxd4qJinVzkNOFZacFZSYVJwaHc/view?usp=sharing
>> >
>> > Monty
>> >
>> > On Tue, Jul 3, 2018 at 4:01 PM, Pete Lancashire <
>> p...@petelancashire.com>
>> > wrote:
>> >
>> >> Is 206 Washington ? I have the remains of a 4051 4052 and 4010 terminal
>> >> sitting outside in the scrap pile. Parts have gone to Europe but
>> they're
>> >> still pieces left over
>> >>
>> >>
>> >> They were about 25 miles west of Portland Oregon.
>> >>
>> >>
>> >>
>> >> On Tue, Jul 3, 2018, 1:35 PM Ian Finder via cctalk <
>> cctalk@classiccmp.org>
>> >> wrote:
>> >>
>> >>> These systems are rare enough that it's probably worth fixing instead
>> of
>> >>> treating the board as a simple FRU. There are schematics on bitsavers
>> for
>> >>> that board, and they are complete.
>> >>>
>> >>> On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk <
>> >>> cctalk@classiccmp.org> wrote:
>> >>>
>> >>> > I've been repairing my Tektronix 4052.
>> >>> >
>> >>> > I've got the digital logic working - but the text and graphics are
>> >>> messed
>> >>> > up.
>> >>> >
>> >>> > I posted photos of the screens in my Tektronix 4052 troubleshooting
>> >>> thread
>> >>> > on vcfed.
>> >>> >
>> >>> > With a scope on the final X amplifier stage - it is oscillating -
>> so I
>> >>> see
>> >>> > weird horizontal strokes instead of dots for text.  I know from the
>> >>> service
>> >>> > manual that this circuit includes a feedback loop, and with the
>> scope
>> >>> I see
>> >>> > oscillation all around the loop - so I haven't found the source.
>> >>> >
>> >>> > Does anyone have a spare Tektronix 4052 (or 4051) Display Board
>> that I
>> >>> > could buy?
>> >>> >
>> >>> > Thanks,
>> >>> > Monty
>> >>> >
>> >>>
>> >>>
>> >>>
>> >>> --
>> >>>Ian Finder
>> >>>(206) 395-MIPS
>> >>>ian.fin...@gmail.com
>> >>>
>> >>>
>> >
>>
>
>

Re: Looking for Tektronix 4051 or 4052 Display Board

[Brent Hilpert via cctalk]

On 2018-Jul-03, at 5:59 PM, Jon Elson via cctalk wrote:
> On 07/03/2018 03:35 PM, Ian Finder via cctalk wrote:
>> On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk <
>> cctalk@classiccmp.org> wrote:
>> 
>>> I've been repairing my Tektronix 4052.
>>> 
>>> I've got the digital logic working - but the text and graphics are messed
>>> up.
>>> 
>>> I posted photos of the screens in my Tektronix 4052 troubleshooting thread
>>> on vcfed.
>>> 
>>> With a scope on the final X amplifier stage - it is oscillating - so I see
>>> weird horizontal strokes instead of dots for text.  I know from the service
>>> manual that this circuit includes a feedback loop, and with the scope I see
>>> oscillation all around the loop - so I haven't found the source.
>>> 
>>> 
> If it is basically working, but just has oscillation, then it is almost 
> certainly a capacitor issue.
> There are likely capacitors in the feedback loop to reduce bandwidth, and 
> decoupling capacitors
> on the power rails.  It would be fairly easy to track down the specific 
> capacitors from the manual and check them.


I had the same initial thought, but Monty's msgs & scope trace show a solid 
ramp waveform down around 37Hz, not the higher F ringing or transient sort of 
sine oscillation
one would expect from failed small-C bypass/suppression/etc. caps. It's more 
like a relaxation-oscillator type of activity. He's already replaced a couple 
of the larger-C caps in the circuit.

Re: Looking for Tektronix 4051 or 4052 Display Board

[Jon Elson via cctalk]

On 07/03/2018 03:35 PM, Ian Finder via cctalk wrote:

On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk <
cctalk@classiccmp.org> wrote:


I've been repairing my Tektronix 4052.

I've got the digital logic working - but the text and graphics are messed
up.

I posted photos of the screens in my Tektronix 4052 troubleshooting thread
on vcfed.

With a scope on the final X amplifier stage - it is oscillating - so I see
weird horizontal strokes instead of dots for text.  I know from the service
manual that this circuit includes a feedback loop, and with the scope I see
oscillation all around the loop - so I haven't found the source.


If it is basically working, but just has oscillation, then 
it is almost certainly a capacitor issue.
There are likely capacitors in the feedback loop to reduce 
bandwidth, and decoupling capacitors
on the power rails.  It would be fairly easy to track down 
the specific capacitors from the manual and check them.


Jon

Re: Looking for Tektronix 4051 or 4052 Display Board

[Brent Hilpert via cctalk]

On 2018-Jul-03, at 5:06 PM, Brent Hilpert via cctalk wrote:
> However, compare to:
>   https://drive.google.com/file/d/1TJjeZqszca1C7XILsnDyO9D_r64ZMwoo/view
> the 2 & 3 pin labels on U184A should be swapped.

Whoops, correction to my correction, they got the pins right, but the +/- input 
labelling should be swapped there.

Re: Looking for Tektronix 4051 or 4052 Display Board

[Brent Hilpert via cctalk]

On 2018-Jul-03, at 1:21 PM, Monty McGraw via cctalk wrote:
> I've been repairing my Tektronix 4052.
> 
> I've got the digital logic working - but the text and graphics are messed
> up.
> 
> I posted photos of the screens in my Tektronix 4052 troubleshooting thread
> on vcfed.
> 
> With a scope on the final X amplifier stage - it is oscillating - so I see
> weird horizontal strokes instead of dots for text.  I know from the service
> manual that this circuit includes a feedback loop, and with the scope I see
> oscillation all around the loop - so I haven't found the source.
> 
> Does anyone have a spare Tektronix 4052 (or 4051) Display Board that I
> could buy?


I take it you are referring to discussion and info from your post on may 27th 
at:

http://www.vcfed.org/forum/showthread.php?63656-Tektronix-4052-Troubleshooting/page2=4051

Re a comment in that discussion:

The feedback loop in the op-amp circuitry is the negative-feedback gain-control 
loop.
If you open that loop the gain will shoot off to -->infinity (in the real 
world, the highest the amplifier can do, the output would go binary 
rail-to-rail).

If you noticing and wondering why the "negative" feedback loops around to the + 
input on the op-amp,
it's because the output drivers provide a stage of inversion (specifically 
Q84/95).

Note there are some mistakes in those Tek schematics around U184A/B. They are 
mixing up the pin numbering and +/- input labelling.
There seems to be half-a-dozen variations on the deflection circuitry (was 
looking also at the 4051 service manual from bitsavers)
and the error seems to morph around between the versions, like someone tried to 
fix it at one point but misunderstood and reintroduced
at another.

On this version you reffed:
https://drive.google.com/file/d/1FQxqfVyOeA1BJjUS7b7X-FzL7Wb8g7q5/view
they get it right.

However, compare to:
https://drive.google.com/file/d/1TJjeZqszca1C7XILsnDyO9D_r64ZMwoo/view
the 2 & 3 pin labels on U184A should be swapped.

On another version on page 96 of the manual they have the +/- flipped on U184B.

Suggestion re the problem:

As you are seeing the oscillation at C196 on the common X/Y bias supply, I 
would try looking at Q186, in particular for a B-C short or leakage.
A B-C short/leakage there would be adding C196 to the X output and could be 
providing the time constant for the ramp/oscillation.
You could try scoping the B & C of Q186, if the signal and voltage levels there 
are similar, consider removing Q186 to resistance check it OOC.

Re: Looking for Tektronix 4051 or 4052 Display Board

[Monty McGraw via cctalk]

Pete,

Thanks for checking on the display board.

Are any of the other boards, power supplies or keyboards left in the 4051
or 4052?

Monty

On Tue, Jul 3, 2018 at 4:19 PM, Pete Lancashire via cctalk <
cctalk@classiccmp.org> wrote:

> -- Forwarded message -
> From: Pete Lancashire 
> Date: Tue, Jul 3, 2018, 2:18 PM
> Subject: Re: Looking for Tektronix 4051 or 4052 Display Board
> To: Monty McGraw 
>
>
> Yeah the two display boards went to Europe.
>
> If anybody needs three perfectly good 11 inch CRTs, deflection yolks
> excetera come to Portland Oregon and they're yours or have somebody pick
> them up for you they're in the scrap pile and scrap is going in about a
> month. Each CRT contains about $35 worth of gold.
>
> On Tue, Jul 3, 2018, 2:12 PM Monty McGraw  wrote:
>
> > Pete,
> >
> > I'm in Texas near Houston.
> >
> > The Display Board is the vertical board to the left of the CRT.  It has
> > several cables at the bottom to pin headers and the cable to the neck of
> > the CRT.
> > It also has connectors to the power transistors that simply unplug when
> > you remove the Display Board.
> >
> > Here is a picture of a display board:
> > https://drive.google.com/file/d/0Bxd4qJinVzkNOFZacFZSYVJwaHc/
> view?usp=sharing
> >
> > Monty
> >
> > On Tue, Jul 3, 2018 at 4:01 PM, Pete Lancashire  >
> > wrote:
> >
> >> Is 206 Washington ? I have the remains of a 4051 4052 and 4010 terminal
> >> sitting outside in the scrap pile. Parts have gone to Europe but they're
> >> still pieces left over
> >>
> >>
> >> They were about 25 miles west of Portland Oregon.
> >>
> >>
> >>
> >> On Tue, Jul 3, 2018, 1:35 PM Ian Finder via cctalk <
> cctalk@classiccmp.org>
> >> wrote:
> >>
> >>> These systems are rare enough that it's probably worth fixing instead
> of
> >>> treating the board as a simple FRU. There are schematics on bitsavers
> for
> >>> that board, and they are complete.
> >>>
> >>> On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk <
> >>> cctalk@classiccmp.org> wrote:
> >>>
> >>> > I've been repairing my Tektronix 4052.
> >>> >
> >>> > I've got the digital logic working - but the text and graphics are
> >>> messed
> >>> > up.
> >>> >
> >>> > I posted photos of the screens in my Tektronix 4052 troubleshooting
> >>> thread
> >>> > on vcfed.
> >>> >
> >>> > With a scope on the final X amplifier stage - it is oscillating - so
> I
> >>> see
> >>> > weird horizontal strokes instead of dots for text.  I know from the
> >>> service
> >>> > manual that this circuit includes a feedback loop, and with the scope
> >>> I see
> >>> > oscillation all around the loop - so I haven't found the source.
> >>> >
> >>> > Does anyone have a spare Tektronix 4052 (or 4051) Display Board that
> I
> >>> > could buy?
> >>> >
> >>> > Thanks,
> >>> > Monty
> >>> >
> >>>
> >>>
> >>>
> >>> --
> >>>Ian Finder
> >>>(206) 395-MIPS
> >>>ian.fin...@gmail.com
> >>>
> >>>
> >
>

Fwd: Looking for Tektronix 4051 or 4052 Display Board

[Pete Lancashire via cctalk]

-- Forwarded message -
From: Pete Lancashire 
Date: Tue, Jul 3, 2018, 2:18 PM
Subject: Re: Looking for Tektronix 4051 or 4052 Display Board
To: Monty McGraw 


Yeah the two display boards went to Europe.

If anybody needs three perfectly good 11 inch CRTs, deflection yolks
excetera come to Portland Oregon and they're yours or have somebody pick
them up for you they're in the scrap pile and scrap is going in about a
month. Each CRT contains about $35 worth of gold.

On Tue, Jul 3, 2018, 2:12 PM Monty McGraw  wrote:

> Pete,
>
> I'm in Texas near Houston.
>
> The Display Board is the vertical board to the left of the CRT.  It has
> several cables at the bottom to pin headers and the cable to the neck of
> the CRT.
> It also has connectors to the power transistors that simply unplug when
> you remove the Display Board.
>
> Here is a picture of a display board:
> https://drive.google.com/file/d/0Bxd4qJinVzkNOFZacFZSYVJwaHc/view?usp=sharing
>
> Monty
>
> On Tue, Jul 3, 2018 at 4:01 PM, Pete Lancashire 
> wrote:
>
>> Is 206 Washington ? I have the remains of a 4051 4052 and 4010 terminal
>> sitting outside in the scrap pile. Parts have gone to Europe but they're
>> still pieces left over
>>
>>
>> They were about 25 miles west of Portland Oregon.
>>
>>
>>
>> On Tue, Jul 3, 2018, 1:35 PM Ian Finder via cctalk 
>> wrote:
>>
>>> These systems are rare enough that it's probably worth fixing instead of
>>> treating the board as a simple FRU. There are schematics on bitsavers for
>>> that board, and they are complete.
>>>
>>> On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk <
>>> cctalk@classiccmp.org> wrote:
>>>
>>> > I've been repairing my Tektronix 4052.
>>> >
>>> > I've got the digital logic working - but the text and graphics are
>>> messed
>>> > up.
>>> >
>>> > I posted photos of the screens in my Tektronix 4052 troubleshooting
>>> thread
>>> > on vcfed.
>>> >
>>> > With a scope on the final X amplifier stage - it is oscillating - so I
>>> see
>>> > weird horizontal strokes instead of dots for text.  I know from the
>>> service
>>> > manual that this circuit includes a feedback loop, and with the scope
>>> I see
>>> > oscillation all around the loop - so I haven't found the source.
>>> >
>>> > Does anyone have a spare Tektronix 4052 (or 4051) Display Board that I
>>> > could buy?
>>> >
>>> > Thanks,
>>> > Monty
>>> >
>>>
>>>
>>>
>>> --
>>>Ian Finder
>>>(206) 395-MIPS
>>>ian.fin...@gmail.com
>>>
>>>
>

Re: Looking for Tektronix 4051 or 4052 Display Board

[Pete Lancashire via cctalk]

Is 206 Washington ? I have the remains of a 4051 4052 and 4010 terminal
sitting outside in the scrap pile. Parts have gone to Europe but they're
still pieces left over


They were about 25 miles west of Portland Oregon.



On Tue, Jul 3, 2018, 1:35 PM Ian Finder via cctalk 
wrote:

> These systems are rare enough that it's probably worth fixing instead of
> treating the board as a simple FRU. There are schematics on bitsavers for
> that board, and they are complete.
>
> On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > I've been repairing my Tektronix 4052.
> >
> > I've got the digital logic working - but the text and graphics are messed
> > up.
> >
> > I posted photos of the screens in my Tektronix 4052 troubleshooting
> thread
> > on vcfed.
> >
> > With a scope on the final X amplifier stage - it is oscillating - so I
> see
> > weird horizontal strokes instead of dots for text.  I know from the
> service
> > manual that this circuit includes a feedback loop, and with the scope I
> see
> > oscillation all around the loop - so I haven't found the source.
> >
> > Does anyone have a spare Tektronix 4052 (or 4051) Display Board that I
> > could buy?
> >
> > Thanks,
> > Monty
> >
>
>
>
> --
>Ian Finder
>(206) 395-MIPS
>ian.fin...@gmail.com
>
>

Re: Looking for Tektronix 4051 or 4052 Display Board

[Ian Finder via cctalk]

These systems are rare enough that it's probably worth fixing instead of
treating the board as a simple FRU. There are schematics on bitsavers for
that board, and they are complete.

On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk <
cctalk@classiccmp.org> wrote:

> I've been repairing my Tektronix 4052.
>
> I've got the digital logic working - but the text and graphics are messed
> up.
>
> I posted photos of the screens in my Tektronix 4052 troubleshooting thread
> on vcfed.
>
> With a scope on the final X amplifier stage - it is oscillating - so I see
> weird horizontal strokes instead of dots for text.  I know from the service
> manual that this circuit includes a feedback loop, and with the scope I see
> oscillation all around the loop - so I haven't found the source.
>
> Does anyone have a spare Tektronix 4052 (or 4051) Display Board that I
> could buy?
>
> Thanks,
> Monty
>



-- 
   Ian Finder
   (206) 395-MIPS
   ian.fin...@gmail.com

Looking for Tektronix 4051 or 4052 Display Board

[Monty McGraw via cctalk]

I've been repairing my Tektronix 4052.

I've got the digital logic working - but the text and graphics are messed
up.

I posted photos of the screens in my Tektronix 4052 troubleshooting thread
on vcfed.

With a scope on the final X amplifier stage - it is oscillating - so I see
weird horizontal strokes instead of dots for text.  I know from the service
manual that this circuit includes a feedback loop, and with the scope I see
oscillation all around the loop - so I haven't found the source.

Does anyone have a spare Tektronix 4052 (or 4051) Display Board that I
could buy?

Thanks,
Monty

Re: Looking for North star software

[Fred Cisin via cctalk]

On Tue, 3 Jul 2018, dwight via cctalk wrote:
I'm not as worried about 10 hard secrtored disk. I still have the punch 
I had made for my H89. I can create 10 sector from old 360K disk.


If you have a working H89 (hard sectored), then you should be able to 
write a program to run on the H89 to write hard sectored disk images!

Can it do single density 256 byte sectors?  or MFM 512 byte sectors?

.ASM for PCTOFLOP should be available, as a guide to what you need, but 
will need modification for the H89 disk controller.


Most of the NorthStar disk images should be availablem once you've got the 
H89 writing disks from them!


Once you've got the NorthStar booting CP/M plus a copy of PIP, you can 
then continue on it.

MOS 6500/1 ROM archival service

[Jim Brain via cctalk]

I realize it's been a while since this happened:

http://e4aws.silverdr.com/hacks/6500_1/

But, I have pulled my hacked reader out from mothballs to read a CPU 
someone is sending, so I thought I would inquire if others have 6500/1 
units that want read.


Jim

--
Jim Brain
br...@jbrain.com
www.jbrain.com

Re: Preserved LGP-30

[Jim Manley via cctalk]

The degradation and attracting bacteria is also why geeks don’t get to
handle humans ... well, the halitosis, body odor, long hair/beards, etc.,
probably don’t help, either! 

All the Best,
Jim

On Tue, Jul 3, 2018 at 9:09 AM js--- via cctalk 
wrote:

>
> Different kind of oils, Christian.  What humans leach isn't
> petroleum-based, and it degrades and carries and attracts bacteria.


> - J.
>

Re: Preserved LGP-30

[js--- via cctalk]

On 7/3/2018 3:58 AM, Christian Corti via 
cctalk wrote:
On Mon, 2 Jul 2018, "j...@cimmeri.com" 
wrote:
Seriously!  Liam, don't you know that 
handling paper with your hands 
transfers oils to it and hastens its 
decay?  This is why gloves are worn 
to handle old paper artifacts.


*lol*
Especially with oiled paper tape that 
is exposed to daylight and much more.


Christian


Different kind of oils, Christian.  What 
humans leach isn't petroleum-based, and 
it degrades and carries and attracts 
bacteria.


- J.

Re: MSV11-J engineering info

[Noel Chiappa via cctalk]

> From: Glen Slick

> There are 88 41256 256Kx1 DRAMs on a 2MB MSV11-J. Each 512KB bank has
> 22 256Kx1 DRAMs organized as 16 data bits plus 6 ECC bits.

Umm, I think the internal organization is paired banks (one for even word
addresses, one for odd); the manual talks about doing double-word reads
(although only one word gets transferred over the bus at a time, but the
PMI has some optimization for double-word cycles, IIRC).

> If someone was sufficiently motivated I suppose they could probe each
> of the 88 DRAMs while writing various bit patterns of data to various
> memory locations and work out the mapping that way. ... I'm not sure
> which would be more work, probing one or a small number of DRAMs at a
> time

Oh, that's an improvement on what I was thinking of as a fall-back, if nobody
has the info (which was to tie the outputs of individual DRAM chips high or
low - depending on how they implement their output stages - through a
suitably-sized resistor, and look to see what effect it had on writing and
then reading - all 0's or 1's, depending on the tie - still a lot less work
than pulling chips :-). Dunno why it wasn't obvious this would be easier! :-)

I would/will just write a two-instruction loop (in the PARs) which writes a
word with only a single '1' bit, hook up a 'scope (I'm too lazy to hook up a
logic analyzer :-) to a DRAM input, and walk the bit through the odd and even
words until I see it on the 'scope.

I thought about doing the ECC bits first, using the maintenance mode (to walk
a '1' through the ECC bits), to avoid getting confused by 1's being written to
them during the above process, but that would be a lot more work, since I'd
have to look at all the chips in the array to find the one that's getting the
'1' ECC bit.

It'll probably be a lot easier to just disable ECC, and write all 0's to all
the ECC bits while doing the data bit discovery (above); once those are done,
the remaining chips are known to be ECC, and I can walk a '1' through the ECC
bits to work them out.

> From a brief look at the manual it might be possible to use diagnostic
> modes to write specific ECC bit patterns and work out the ECC bit
> mappings as well.

Yup, that was my take too. Although I'm having to re-read the manual a few
times to fully grok how all the various mode bits interact!

> Might be very tedious, so might need lots of motivation.

I think that using the procedure above, it'll go reasonably quickly,
actually; the more bits I ID, the fewer values I'll have to try on each
succeding DRAM chip.

> If I ever get really bored some day maybe I'd take a look and try to
> see just how tedious it might be.

I'm going to need this info real soon (to hopefully fix a broken MSV11-J),
so I'll probably start on this later today if nobody has the info.

I'll add the info to the MSV11-J page on the CHWiki, once I have it.

Noel

Re: Looking for North star software

[dwight via cctalk]

I'm not as worried about 10 hard secrtored disk. I still have the punch I had 
made for my H89. I can create 10 sector from old 360K disk.

Dwight



From: cctalk  on behalf of allison via cctalk 

Sent: Tuesday, July 3, 2018 6:05:23 AM
To: cctalk@classiccmp.org
Subject: Re: Looking for North star software

On 07/02/2018 11:31 PM, Fred Cisin via cctalk wrote:
>>> BUT, the Horizon can also manage 8" drives (SSSD soft-sector CP/M
>>> standard!) with appropriate controller, or use other S100 FDC boards.
>
> On Mon, 2 Jul 2018, allison via cctalk wrote:
>> Really? not any of the MDS (SD or DD) controllers as they only know hard
>> sector.A Soft sector controller with rom
>> on board then the situation changes.  Plan B is  a CPU with local eprom
>> and use that as the system monitor to boot
>> stuff to disk.
>> The standard NS controllers have only a small rom enough to boot a NS SD
>> or DD floppy using their controller
>> where the roms are.
>> . . . �   The older
>> of mine runs a MDC4 765 based soft sector
>> controller and is an active highly modded CPM system.  The other is
>> vanilla and tucked away.
>
> Really, I just assumed that you could install a non-NorthStar disk
> controller, in addition to the stock one, or maybe instead, in order
> to be able to do soft-sector.
You can but none of the NS* software will recognize it and it
effectively makes the Horizon just another nice S100 crate.
The NS* software is well wrapped around the hard sector controller which
is actually crude but effective.
Unplug the disk controller and the system has no rom or front panel.

Its why I have two.  One is a basic 56K NS horizon where the only board
not NS* is the static 64K ram card.
The other is NS* horizon box and mother board aka the bus has all the IO
for serial, parallel and
hearbeat interrupt at one end. But a faster Z80 card (10MHZ modded
compupro) 256K of ram,
hard disk controller, soft sector controller (765based) and several
slave controllers for moving
stuff and printer buffering.

A lot of the NS systems were improved with soft sector controllers and a
phantom rom card if the
controller didn't have one.  The box was good quality fair cooling and a
beefy power supply.

Allison

Re: Looking for North star software

[allison via cctalk]

On 07/02/2018 11:31 PM, Fred Cisin via cctalk wrote:
>>> BUT, the Horizon can also manage 8" drives (SSSD soft-sector CP/M
>>> standard!) with appropriate controller, or use other S100 FDC boards.
>
> On Mon, 2 Jul 2018, allison via cctalk wrote:
>> Really? not any of the MDS (SD or DD) controllers as they only know hard
>> sector.    A Soft sector controller with rom
>> on board then the situation changes.  Plan B is  a CPU with local eprom
>> and use that as the system monitor to boot
>> stuff to disk.
>> The standard NS controllers have only a small rom enough to boot a NS SD
>> or DD floppy using their controller
>> where the roms are.
>> . . . �   The older
>> of mine runs a MDC4 765 based soft sector
>> controller and is an active highly modded CPM system.  The other is
>> vanilla and tucked away.
>
> Really, I just assumed that you could install a non-NorthStar disk
> controller, in addition to the stock one, or maybe instead, in order
> to be able to do soft-sector.
You can but none of the NS* software will recognize it and it
effectively makes the Horizon just another nice S100 crate.
The NS* software is well wrapped around the hard sector controller which
is actually crude but effective.
Unplug the disk controller and the system has no rom or front panel. 

Its why I have two.  One is a basic 56K NS horizon where the only board
not NS* is the static 64K ram card.
The other is NS* horizon box and mother board aka the bus has all the IO
for serial, parallel and
hearbeat interrupt at one end. But a faster Z80 card (10MHZ modded
compupro) 256K of ram,
hard disk controller, soft sector controller (765based) and several
slave controllers for moving
stuff and printer buffering.   

A lot of the NS systems were improved with soft sector controllers and a
phantom rom card if the
controller didn't have one.  The box was good quality fair cooling and a
beefy power supply.

Allison

Re: Revealing a new project (non-VCF)

[Tony Duell via cctalk]

On Mon, Jul 2, 2018 at 11:09 PM, Evan Koblentz via cctalk
 wrote:
> Time to reveal a personal project related to vintage computing and unrelated
> to my role at VCFed.
>
> In the past two years, while getting neck-deep in the historic Lego 9700
> "Technic Control Center" set, I learned that there is a TON of information
> about this set (and about various related sets) -- but most of that
> information is missing from the web or at best scattered.
>
> What these programmable robotic sets all have in common is they're all from
> the 10 years BEFORE the modern Mindstorms series, and they run on vintage
> computers!
>
> I decided a few months ago to make a web site about it. I call the site
> www.mindsbeforethestorm.com. The site is under construction but you can
> visit now and see where it is going.

One thing struck me from looking at your schematic of the Apple ][ interface
card (you know me, always looking at the schematics first...)

That card is essentally a 6522 VIA with port B linked to a 20 pin header. The
BBC micro has a user port which is port B of a 6522 linked to a 20 pin header,
and I've just checked the 'Advanced User Guide' and the connections are
essentially a superset of those on your Apple ][ board (pns 2 and 4 would be
the CB1 and CB2 lines on a BBC).

It is my guess that the BBC micro version of this system used the Lego
interface box, but connected it straight to the user port on the BBC.

-tony

Revealing a new project (non-VCF)

[Evan Koblentz via cctalk]

Time to reveal a personal project related to vintage computing and 
unrelated to my role at VCFed.


In the past two years, while getting neck-deep in the historic Lego 9700 
"Technic Control Center" set, I learned that there is a TON of 
information about this set (and about various related sets) -- but most 
of that information is missing from the web or at best scattered.


What these programmable robotic sets all have in common is they're all 
from the 10 years BEFORE the modern Mindstorms series, and they run on 
vintage computers!


I decided a few months ago to make a web site about it. I call the site 
www.mindsbeforethestorm.com. The site is under construction but you can 
visit now and see where it is going.


I'm asking for contributions to the project.

I make a very modest living through my work as a freelance tech 
journalist and additionally through VCFed fundraising. Many of you will 
also recall that a personal fundraiser is what enabled publishing of my 
computer history book in 2015. That was a positive experience.


I do not plan to sell anything on this new site, only to offer helpful 
information that isn't currently available or is very difficult to find. 
As such, I cannot promise any Kickstarter-style rewards: I don't have 
any ideas about what a good reward for this might be (open to 
suggestions). Instead, I appeal to your altruism: fund this project 
because it is a good thing.


Please visit my new site. If you think it exemplifies how the web should 
be used, if you'd like to see it get finished, and if you would like me 
to continue to be able to pay my rent and eat food, then please make a 
contribution via https://fundrazr.com/61N3ef?ref=ab_74VRia.


Thanks,
-Evan

Re: Preserved LGP-30

[Liam Proven via cctalk]

On Tue, 3 Jul 2018 at 12:08, Bill Degnan via cctalk
 wrote:

>
> And wouldn't it be possible that tape strewn artistically is just that, a
> prop?  Especially given the pattern on the tape?   Who would display the
> real thing that way?

Exactly! :-) It looked like a dummy to me, artfully arranged.

Also, AFAICT, it was very new tape. If it was original, aged, and had
any visible data, I literally wouldn't have touched it.

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: Preserved LGP-30

[Bill Degnan via cctalk]

On Tue, Jul 3, 2018, 4:58 AM Christian Corti via cctalk <
cctalk@classiccmp.org> wrote:

> On Mon, 2 Jul 2018, "j...@cimmeri.com" wrote:
> > Seriously!  Liam, don't you know that handling paper with your hands
> > transfers oils to it and hastens its decay?  This is why gloves are worn
> to
> > handle old paper artifacts.
>
> *lol*
> Especially with oiled paper tape that is exposed to daylight and much
> more.
>
> Christian
>

And wouldn't it be possible that tape strewn artistically is just that, a
prop?  Especially given the pattern on the tape?   Who would display the
real thing that way?

Bill

>

Re: Preserved LGP-30

[Christian Corti via cctalk]

On Mon, 2 Jul 2018, "j...@cimmeri.com" wrote:
Seriously!  Liam, don't you know that handling paper with your hands 
transfers oils to it and hastens its decay?  This is why gloves are worn to 
handle old paper artifacts.


*lol*
Especially with oiled paper tape that is exposed to daylight and much 
more.


Christian