Anyone already build this kit?

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zxhenk
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Joined: Tue May 05, 2020 11:32 am

Anyone already build this kit?

Post by zxhenk »

I found this https://www.budgetronics.eu/en/building ... a-25781-20
Seems like a nice kit but will be a lot of soldering. Does anyone has experience with this kit?
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msch
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Location: Frankfurt/M, Germany

Re: Anyone already build this kit?

Post by msch »

I am wondering - you „found this“ in Your own store? You are the designer and the owner of the linked store...

Tell us more about Your project. What was the design goal and why did You choose this strange form factor?
What are the differences to the full version of ZXpand? Is it possible to update the firmware?
I cannot find any connectors/header for the original keyboard membranes. Will it be possible to connect an external keyboard solution?
Do You offer support for the project?
Mathias

ZX-Team member and classic computer collector
zxhenk
Posts: 18
Joined: Tue May 05, 2020 11:32 am

Re: Anyone already build this kit?

Post by zxhenk »

:D Well spotted :D

This was born as a hobby project for myself and not as a commercial endeavour where I wanted a ZX81 with a zxpand extension, keyboard, joystick interface, internet module ( as used and invented by Siggi) as one compact PCB to form a more robust design without wobbly connectors between parts.

After a few pcb revisions I finally finished it and I made just a few kits to see if there is interest in this for other zx81 fans. There will not be a big amount of these kits because it is a lot work to make them so it will be a small batch just for others who are interested. Or it must be a great succes but I doubt there are a lot of people who want to build such an old retrocomputer like the ZX81 , maybe a handfull.

The zxpand version for this one was done by Sirmorris but works the same as the standard zxpand so with the same update scheme. He has made a special version for this build with its own startup message.

There is no keyboard connection because that was not the purpose of this build. The keyboard is integrated. It is bigger then a normal zx81 and will not fit in a zx81 case.

By support what do you exactly mean? A working kit design is what is offered and help and advice if after construction it does not startup. But if all is done as described and the soldering is done well it will work right away.
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siggi
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Re: Anyone already build this kit?

Post by siggi »

Is there a schema of the board?
32KB is enough ram for a lot of ZX81 applications. But having 40KB ram, it would be possible to use more ZeddyNet applications, which run above 32K and are 16K in size. So I would need to add more ram ....

Siggi
My ZX81 web-server: online since 2007, running since dec. 2020 using ZeddyNet hardware
http://zx81.ddns.net/ZxTeaM
zxhenk
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Joined: Tue May 05, 2020 11:32 am

Re: Anyone already build this kit?

Post by zxhenk »

Hi Siggi,

I have tried IRC chat, Ping, visited bulletin boards and so on with zeddynet and they all worked well. More memory would be nice but I am not sure this can be done that easy with this setup. The schematic I have is not cleaned up very well and not yet ready to publish at the moment but I have a better idea.
If you PM me with your address I will sent you a completly build and working early revsion board for you to keep so you can experiment with it for free. Because you are the deisgner of Zeddynet. I also gave away one to Sirmorris for the zxpand design.
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msch
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Re: Anyone already build this kit?

Post by msch »

Great to hear that Sirmorris was involved!
Regarding Your support: I asked because I could not find any contact or support information in the construction manual.
One support question has already been asked (zxpand firmware / update process).
Mathias

ZX-Team member and classic computer collector
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