PCB wiring plots on clear plastic

On Sunday, 15 September 2019 17:51:19 UTC+1, jla...@highlandsniptechnology.com wrote:

On Sat, 14 Sep 2019 09:04:01 -0700 (PDT), tabbypurr wrote:
On Saturday, 14 September 2019 16:31:59 UTC+1, jla...@highlandsniptechnology.com wrote:
On Sat, 14 Sep 2019 04:27:54 -0700 (PDT), tabbypurr wrote:
On Saturday, 14 September 2019 03:57:46 UTC+1, jla...@highlandsniptechnology.com wrote:
On Sat, 14 Sep 2019 01:56:10 +0000 (UTC),
DecadentLinuxUserNumeroUno@decadence.org wrote:
John Larkin <jlarkin@highland_atwork_technology.com> wrote in
news:kaknne9mhnak6v0i9jkgj658894v1t5cc6@4ax.com:

Early IC designs were hand-cut from rubylith on mylar. To simplify
life, there were exactly 25 microns to the mil in Silicon Valley..

I remember the traces being rounded in the early IC layout days. No
sharp corners, even at the anular ring matings. All smooth. If we
could have had rounded edges on the traces themselves, we would have!
Little oval traces running all around... nice and quiet.

Some people made rounded bends with the black tape on mylars, but that
tended to creep over time. We overlapped at an angle and cut, so one
trace wound up being a bunch os segments.

bending it round was quicker, but there wasn't always enough space. One thing I liked about acetate & crepe was that tracks could be narrowed where they had to squeeze through narrow spaces, and pads trimmed down to accommodate. Of course narrow meant enormous by today's standards.

It was an accomplishment to push two traces between DIP pads. I was
never brave enough to do that. One was tricky enough.

yeah Now I look at early 80s boards and wonder what folk were thinking leaving so much of the space bare.

It's funnny to see news articles about technology. They use old stock
photos of 2-layer board full of dips and thru-hole parts.

Software still has images of floppies for 'save'.

Doing logic in FPGAs is a big improvement. Multilayer boards is
another huge improvement.

I wonder if people will still be soldering parts to PC boards 100
years from now. Probably so.

I'm convinced they won't. A whole appliance will be done in one silicon chip, even at the hobby scale. Silicon because it's so cheap & abundant. I doubt anything will fail to have embedded electronics.

Things will still need wires and stuff. You can't bolt a BGA ASIC into
a box.

The case will be moulded around the chip, or perhaps the chip's epoxy package will also be the case. External connectors will spot weld direct to the chip pads. Or maybe connectors will be within the chip's epoxy.

PCBs make zero sense in 100 years. A single chip can contain all the electronics, everything else can at worst connect direct to it. PCBs are just an artifact of our inability to put the whole lot in 1 chip.

The idea that small scale production will remove the option to do custom chips also makes no sense in 100 years. Building electronics will be just like sending gerber files to china, and you get your product in the post. There will be no reason to do things our primitive way with discretes.

Bill missed all this of course.

I remember the days when even DIL pads were too close, and QIL was a thing. Lots of QIL chips got their legs pliered to fit DIL sockets later.


It was a huge PITA. Literally a PITA, hunched over a light table for
days and weeks. Then two round-trips to Lorry Ray in Mountain View, to
drop off the mylars and pick up the film.

Documents, like manuals, were similarly inefficient. Write in
longhand, give to a secretary to type, correct that a few iterations.

...get peed off with the secretary etc. With hindsight the idea that one had to get someone else to type something seems absurd.

Early in the PC days, it was accepted that "you'll never get a
businessman to type." Now there are no secretaries. Good; it was
demeaning, and a huge waste of human resources, to delegate so many
women to typing and filing and licking stamps and making coffee.

It was crazy. This attitude was even worse... how far society has come
https://www.youtube.com/watch?v=iMuZI5kmpVU


NT

I just read a cool book, Code Girls.

https://www.amazon.com/Code-Girls-Untold-American-Breakers/dp/0316352543/ref=sr_1_2?crid=1ZQ6O0DBLN22G&keywords=code+girls&qid=1568565869&s=books&sprefix=code+girls%2Caps%2C198&sr=1-2

One of them would read encoded German diplomatic messages as they came
in. She had memorized the code books and could do the goofy-modulo
additives math in her head. One really cute, young, innocent looking
kid broke a major Japanese code.

A culture that restricts women is at a 50% disadvantage. At least.

It's insane, beyond stupid. Yet that's how the world is run.


NT