New ZX80 boards

[zx81jens]

I would get another one anyway

[RWAP]

Hi Lee - I have the drawings for the membrane with measurements which I can email to you if this is something you would like to investigate.

Just send me a pm with your email address

Rich

[uk7of9]

Hi there,

i am also interested in a zx80 Board. Any more details about the pricing and the shipping costs to germany ?

Thanks
udo

[Paul]

Whenever there will be new boards in the pipeline, there will be a collective order from germany organized in the Forum of the german ZX-Team. The link
http://forum.tlienhard.com/phpBB3/viewt ... ?f=2&t=351
will show you the thread to watch in order to participate.

Greetings from Germany
Paul

[zx81jens]

hi users!

thank you RICH for sending the ZX80-foil so fast - it fits perfectly to the original ZX80 and also for the ZX80-LEGACY (i might say 99%). it´s a very professional production!

i will show it at the next ZX-MICROFAIR in germany (15.-17.April 2011) !!!

greetings
jens

[Lee Hart]

Paul asked if I could lay out my Legacy ZX80 board to use either the original Sinclair membrane keyboard (using Rich's new overlay), or the individual switches. I think it would be very difficult, but I'll look into it.

One problem is that the traces would need to be gold plated if you expected them to last any length of time. I am somewhat prejudiced against the Sinclair membrane keyboard because that's what failed in both of my original ZX80's.

The keyboard on my Legacy ZX80 is designed so it can be removed. It may be better to make a separate board for use with Rich's membrane overlay. It would be smaller, and so cheaper to get made.

Paul also said that Rich's membrane overlay fit the original ZX80 perfectly, and was "99%" for the Legacy ZX80. What dimensions are off? I can fix that pretty easily.

[Paul]

Paul also said that Rich's membrane overlay fit the original ZX80 perfectly, and was "99%" for the Legacy ZX80.

That was Jens. I asked him the same question, but I have no reply up to now.
Maybe it is safer to use the dimensions Rich offered you, they will be 100% exact.
Just give him a PN with your Email-adress and he will send them to you.
I like the idea of the seperate Keyboards. But we need some mechanism to get them attached to the mainboard for the "real" feeling.
Maybe both versions could be detached from the mainboard in order to have the choice which one to take.
I would not like to have to cut off the switchpart from my mainboard myself, but would like to order both keyboards

[Lee Hart]

RWAP sent me the dimensioned drawing for his ZX80 keyboard overlay. I compared it to my Legacy ZX80 layout, and they are very close indeed! The differences are probably the result of converting inches to cm, and from me scaling dimensions from the online photos I had available. Please forgive me for working in inches...

RWAP keyboard 2.709h x 6.161w, keys spaced 0.551h x 0.551v
My ZX80 board 2.750h x 6.125w, keys spaced 0.550h x 0.575v

I think I can change the PCB layout so it will accept either the tactile switches, or RWAP's foil overlay. However...

1. I have to push the tactile switches closer together vertically. This makes the pins of
the switches so close together that their pads overlap and their holes almost touch.
This is a layout rule violation that increases the chance of defective boards (may
have to pay for 50 to get 40 good ones, for example).

2. The board size and hole locations move. This means the tooling for the present
boards is discarded, and we have to pay the setup charges again (about $160 US)
for the next batch of boards.

3. It's a lot of work to move everything around and add the "interlocking fingers" to the
layout so the foil overlay will work as a keyboard. Before I do, I want to be sure that
people are serious about using the RWAP foil overlay. Otherwise, we're increasing
the cost of the board for no purpose.

Thoughts?

[Paul]

Hi Lee
me personally love to have both variants which makes it two additional boards instead of one for me.
The price itself isn't the issue as this istn't a OLPC Project.
Of course leaving it the way it is, doesn't make it a "no go" the new layout would only be a nice to have.
I would even not care if there were no "cure" for the "Keyboard problem" As it is easily possible to find chips that work fine if you use sockets.
I still have your idea in mind to produce an additional keyboard PCB for the RWAP keyboard.
Would there be high extra cost if you would design the ZX80 board without keyboard or to have it cut off by default?
We could use 90 degree connectors on both sides to have the keyboards attached by plug and play without cable.
I am going to ask in the german forum today and will give you the cummulated feedback.

[sirmorris]

I think having an RWAP membrane option is a great idea. I am in favour of having 2 variants of board - one for tact only and one for membrane only. Personally I too would happily have one of each The membrane version would appeal to people of a more purist disposition.

At the end of the day I think you need to search your soul, Lee If you have any more time patience and inclination then I think you would find the world will have an appetite for a membrainy legacy.

The tact switch version is more modern and possibly more usable, but it does lack a certain authenticity and making a workable overlay for the keys is a problem. Not a stopper for sure, but still something which I feel justifies the extra investment in V2.0...

On another note - I'm going to start removing chips and adding sockets to try and address the killer key problem. Which chips should I target first?

Regards

C