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From: AM on 8 Jul 2010 15:01
On Thu, 08 Jul 2010 11:24:55 -0700, Robert Baer <robertbaer(a)localnet.com>
wrote:

>Jan Panteltje wrote:
>> On a sunny day (Wed, 7 Jul 2010 18:24:25 -0700 (PDT)) it happened
>> "langwadt(a)fonz.dk" <langwadt(a)fonz.dk> wrote in
>> <ed6abd35-6586-4594-8408-efc8d58b64c8(a)j8g2000yqd.googlegroups.com>:
>>
>>> http://upload.wikimedia.org/wikipedia/commons/3/37/Dolby_SR_breadboard.jpg
>>>
>>>
>>>
>>> -Lasse
>>
>> At least somebody had patience...
>> Wonder what the bottom side looks like...
>>
>> Here one of mine:
>> ftp://panteltje.com/pub/z80/graphics_card_top.jpg
>> ftp://panteltje.com/pub/z80/graphics_card_bottom.jpg
> What did you use for the background?
> It seems better than a rug or towel.

That's the shittiest wiring job I have ever seen in my life.
From: Jan Panteltje on 8 Jul 2010 15:01
On a sunny day (Thu, 08 Jul 2010 11:10:47 -0700) it happened Robert Baer
<robertbaer(a)localnet.com> wrote in
<696dnRR3ybgDiavRnZ2dnUVZ_hOdnZ2d(a)posted.localnet>:

>Jan Panteltje wrote:
>> On a sunny day (Wed, 7 Jul 2010 18:24:25 -0700 (PDT)) it happened
>> "langwadt(a)fonz.dk" <langwadt(a)fonz.dk> wrote in
>> <ed6abd35-6586-4594-8408-efc8d58b64c8(a)j8g2000yqd.googlegroups.com>:
>>
>>> http://upload.wikimedia.org/wikipedia/commons/3/37/Dolby_SR_breadboard.jpg
>>>
>>>
>>>
>>> -Lasse
>>
>> At least somebody had patience...
>> Wonder what the bottom side looks like...
>>
>> Here one of mine:
>> ftp://panteltje.com/pub/z80/graphics_card_top.jpg
>> ftp://panteltje.com/pub/z80/graphics_card_bottom.jpg
> Did Ma Bell give you a thousand feet of 50-pair cable?

Yep, it is from an old phone cable IIRC.


> Isn't there a lot of ringing and cross-talk, or is the clock rate low
>for a slow-scan system (FAX or weather)?

It is an 18 MHz xtal, nothing slow scan about it, 80 characters at normal TV resolution 15625 Hz / 30 Hz.
You needed a very good TV monitor for that, a TV set would not be able to display 80 characters.
The CRT controller is the famous Motorola 6845
http://en.wikipedia.org/wiki/Motorola_6845
It is capable of a lot of standards.
Even had a light pen input.

Actually below about 30 MHz, the TTL 'limit' so to speak, wiring like this works just fine.
the capacitance between wires is very small.
Most of the signals on the board are slower anyways, only the shift register that
shifts out the pixels runs at full (pixel) clock.
The big 64 pole DIN connector is actually compatible with the old 'Elector' (then Elektuur) bus.
The processor board was a 4 MHz z80:
ftp://panteltje.com/pub/s/z80_board.jpg
I know it is out of focus, will have to make a new picture one of these days.

The wiring is on the backside with stripped flatcable.
ftp://panteltje.com/pub/s/wiring1.jpg

The whole thing runs my own OS, a CP/M clone, written in asm.

I made many more cards, filled up 2 backplanes.

From: legg on 8 Jul 2010 19:25
On Thu, 08 Jul 2010 01:01:15 -0700, Robert Baer
<robertbaer(a)localnet.com> wrote:

>langwadt(a)fonz.dk wrote:
>> http://upload.wikimedia.org/wikipedia/commons/3/37/Dolby_SR_breadboard.jpg
>>
>>
>>
>> -Lasse
> Must be analog, and have some problems as-is: a) go up one "add-on"
>board on the right and notice one IC half-way plugged in; b) go above
>the second "add-on" board on the right and see a BAER wire shaped like a
>lower-case "e"; that is the you-know-what worst browser that
>Monstor$tomper (or any other "programmer") made.

You might be confused by the 6-pin devices installed in 8-pin sockets;
opto-fets probably.

Nobody said it still worked, but you might be surprised.

RL
From: Grant on 8 Jul 2010 20:52
On Thu, 08 Jul 2010 18:25:47 -0500, legg <legg(a)nospam.magma.ca> wrote:

>On Thu, 08 Jul 2010 01:01:15 -0700, Robert Baer
><robertbaer(a)localnet.com> wrote:
>
>>langwadt(a)fonz.dk wrote:
>>> http://upload.wikimedia.org/wikipedia/commons/3/37/Dolby_SR_breadboard.jpg
>>>
>>>
>>>
>>> -Lasse
>> Must be analog, and have some problems as-is: a) go up one "add-on"
>>board on the right and notice one IC half-way plugged in; b) go above
>>the second "add-on" board on the right and see a BAER wire shaped like a
>>lower-case "e"; that is the you-know-what worst browser that
>>Monstor$tomper (or any other "programmer") made.
>
>You might be confused by the 6-pin devices installed in 8-pin sockets;
>opto-fets probably.

I think it was hanging out along one side, half the pins out of socket.
>
>Nobody said it still worked, but you might be surprised.

The labels look old and faded?

Grant.
From: Grant on 8 Jul 2010 20:56
On Thu, 08 Jul 2010 19:01:17 GMT, Jan Panteltje <pNaonStpealmtje(a)yahoo.com> wrote:

>On a sunny day (Thu, 08 Jul 2010 11:10:47 -0700) it happened Robert Baer
><robertbaer(a)localnet.com> wrote in
><696dnRR3ybgDiavRnZ2dnUVZ_hOdnZ2d(a)posted.localnet>:
>
>>Jan Panteltje wrote:
>>> On a sunny day (Wed, 7 Jul 2010 18:24:25 -0700 (PDT)) it happened
>>> "langwadt(a)fonz.dk" <langwadt(a)fonz.dk> wrote in
>>> <ed6abd35-6586-4594-8408-efc8d58b64c8(a)j8g2000yqd.googlegroups.com>:
>>>
>>>> http://upload.wikimedia.org/wikipedia/commons/3/37/Dolby_SR_breadboard.jpg
>>>>
>>>>
>>>>
>>>> -Lasse
>>>
>>> At least somebody had patience...
>>> Wonder what the bottom side looks like...
>>>
>>> Here one of mine:
>>> ftp://panteltje.com/pub/z80/graphics_card_top.jpg
>>> ftp://panteltje.com/pub/z80/graphics_card_bottom.jpg
>> Did Ma Bell give you a thousand feet of 50-pair cable?
>
>Yep, it is from an old phone cable IIRC.
>
>
>> Isn't there a lot of ringing and cross-talk, or is the clock rate low
>>for a slow-scan system (FAX or weather)?
>
>It is an 18 MHz xtal, nothing slow scan about it, 80 characters at normal TV resolution 15625 Hz / 30 Hz.
>You needed a very good TV monitor for that, a TV set would not be able to display 80 characters.
>The CRT controller is the famous Motorola 6845
> http://en.wikipedia.org/wiki/Motorola_6845
>It is capable of a lot of standards.
>Even had a light pen input.
>
>Actually below about 30 MHz, the TTL 'limit' so to speak, wiring like this works just fine.
>the capacitance between wires is very small.
>Most of the signals on the board are slower anyways, only the shift register that
>shifts out the pixels runs at full (pixel) clock.
>The big 64 pole DIN connector is actually compatible with the old 'Elector' (then Elektuur) bus.
>The processor board was a 4 MHz z80:
> ftp://panteltje.com/pub/s/z80_board.jpg
>I know it is out of focus, will have to make a new picture one of these days.
>
>The wiring is on the backside with stripped flatcable.
> ftp://panteltje.com/pub/s/wiring1.jpg
>
>The whole thing runs my own OS, a CP/M clone, written in asm.

I assembled several Ferguson BigBoard z80 based cp/m kits back then,
wrote some stuff in assembler for it, even the SIO code for one of
the then popular comms programs which was picked up by others. Also
a keyboard 'macro' buffer stuffer. Remember when adding special
functions to keys was the rage? Cp/m and ms-dos had it, died out
alter.
>
>I made many more cards, filled up 2 backplanes.

Ugh, I moved to embedded controllers at the small end of town, even
a mask programmed CPU which flew first try, back in late '84.

Grant.
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