[Coco] new mylars

[Al Hartman]

I don't know that this makes any difference, but in the Timex/Sinclair 
market there have been several runs of the ZX-81 / TS-1000 replacement 
keyboards, and Spectrum replacement mylars.

Many have gone to Brazil, and to the U.K.

Eventually, every mylar is going to dry out and crack. So, it's worth doing. 
I wonder what would happen if packs of 5 were offered on eBay once they were 
done?

I bet there are lots of Cocos with dead keyboards out there. Has anyone 
posted an interest thread on 
http://www.vintage-computer.com/vcforum/forumdisplay.php?46-Tandy-Radio-Shack 
?

-[ Al ]-

-----Original Message----- 
From: Boisy G. Pitre

At Cloud-9, we looked into this. There are really two options:

Option 1. A scan of the original mylar sheet, cleaning up in Photoshop, then 
having it duplicated on mylar with conductive ink.
Option 2. Relayout the entire keyboard mylar with Eagle or a similar tool, 
let the autorouter figure out the placement of the traces, and then submit 
gerbers. This seems to be a more durable and flexible option.

In both cases, care must be taken to get the size exactly right. The 
additional gotchas are the screw holes which must exactly align in the 
proper places when the mylar is folded.

There’s also the plastic sheet insert that goes between the folded mylar. It 
also has specific holes for allowing the key contacts to go through as well 
as the screw holes.

Also there must be a rigid plastic piece glued onto the tail that is 
inserted into the 16 pin connector on the motherboard.

All in all, to get it right would be very tedious.

In the end, we came to the conclusion that the minimum order quantity that 
would be required along with the effort to properly duplicate the keyboard 
mylar (option 2 above) would be considerable when weighed against the 
availability of things like the PS/2 keyboard interface.
—
Boisy G. Pitre
CoCo Projects Coordinator
http://www.cloud9tech.com <http://www.cloud9tech.com/>
http://www.nitros9.org <http://www.nitros9.org/>
http://sourceforge.net/projects/drivewireserver/ 
<http://sourceforge.net/projects/drivewireserver/>
http://sourceforge.net/projects 
<http://sourceforge.net/projects/drivewireserver/>/toolshed
http://liber809.blogspot.com <http://http//liber809.blogspot.com>
http://github.com/boisy/DriveWire-MacServer

> On Aug 11, 2015, at 10:04 AM, Brian Blake <random.rodder at gmail.com> wrote:
>
>
> I think price will be the deciding factor for all of us. I'd like to have 
> a dozen or so mylar sets, but, we'll see what Josh's contact can get us. 
> I'm not convinced yet that this can be done unless we have several hundred 
> sets ordered.
>
> I've sent Josh pics of the mylar, some with a tape measure to give idea of 
> the size of the mylar pieces. Hopefully w can get some good news.
>
>
> Brian