Homebrew PCBs

I suspect the part you were referring to is the 6845, the CRT chip used in
the first IBM PCs.

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Friday, March 18, 2016 2:58 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] TV Typewriter: Custom G10 copper clad

 

  

On Fri, 18 Mar 2016 13:36:03 -0700, you wrote:

<snip>
>Anyway, I know I could get away with being inexact here. But the point of
the exercise is to get as close to original as possible, which is why I went
to the trouble of getting 1973 vintage chips. I'd also like to duplicate the
process a hobbyist of that day would have used also, for my own education
and experience. The experience is a big part of this. I want to be able to
do what the museum can't/won't, let people see and use and get the feel for
the thing. The museum will never show the most important part of the TVT,
the boards, but I can with mine. And because I can I will, and I guess for
that reason I want them to look right.
>

Then a suggestion I'd have would be to go do what you want, but be
reasonable about the definition of "as reasonable". I think that the
comment about the different variations having possibly different color
boards is realistic, although I don't remember any SWTP product that I
saw having paper boards (although there were a lot out there).

NEXT: I'd design the same thing using modern technology, and build
one of them. That would give people a unique idea of just how far
technology has come in about 50 years. (note: feel free to embellish,
but have the basic mode be exactly what the original did).


I seem to remember a 68045 chip that was designed to be a similar
style of display.

Harvey

>From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
>Sent: Friday, March 18, 2016 10:35 AM
>To: Homebrew PCBs <Homebrew_PCBs@yahoogroups.com>
>Subject: Re: [Homebrew_PCBs] TV Typewriter: Custom G10 copper clad
>
> 
>
> 
>
>Yeah
>
> And besides, there are scant few folks around in hobby electronics
nowadays that have ever actually
>
>laid eyes on a finished (or unfinished) Lancaster TV Typewriter. It is
totally obsolete by todays standards and state
>
>of the art.
>
> 
>
>And, as Lancaster envisioned, the thing was to be enclosed in a kind of
wooden desk-top enclosure, so 
>
>nobody sees the circuit boards anyway.
>
> 
>
>Too bad that a search can't somehow be made on the internet, inquiring if
there is some 
>
>"old-timer" (like me) that has a Lancaster TV Typewriter in a dusty pile of
forgotten projects,
>
>and that way, you could get the "real" item and bring it back online.
>
> 
>
>These are just suggestions.........now, don't everbody jump on me with
snide remarks.
>
> 
>
>Regards. 
>
> 
>
>Roland F. Harriston, P.D.
>
>***************************
>
> 
>
> _____ 
>
>From: "Stefan Trethan stefan_trethan@... [Homebrew_PCBs]"
<Homebrew_PCBs@yahoogroups.com>
>
> 
>
>Snip:
>
>Most people are going to look at you as if you are crazy for wanting a
specific colour and weave of material. That is because you are crazy of
course, and nothing to worry about.
>
> 
>
>It will not help your quest at all, but consider buying double sided
laminate (with copper on both sides). I found it much easier to obtain and
just etch one side away completely for single sided boards. Of course it
makes impossible to see the inside.
>
> 
>
>Also mind that in any case the copper on the other side will severely
change the colour you see, even if the seller provides a photo of the board
side. The copper layer is actually a dark red underneath, completely
different colour from the shiny top surface.
>
> 
>
>ST
>
> 
>
>