Repairing Keyboard on Timex Sinclair 1000 ZX81 Computer

You might be able to fix the keyboard on your Timex Sinclair 1000 or Sinclair ZX81 Computer and have it working again!
The paper thin ribbon cable touches the Ram chip because of design error. The Ram chip (among other duties) holds everything you type. It gets rather hot and constant heating cooling causes the ribbon to eventually fail at the ribbon's contact point with Ram chip. The original ribbon end was thickened just at the end where it slips in. The sinclairs I've fixed have still fit tightly back together. But if you feel yours is too loose, glue a piece of the blank ribbon you cut off to the back side of the ribbon end to thicken it. But make sure you don't glue it on the wrong side or there will be no contact at all. haahaa!
Great web sites for Sinclair zx81 (1000)
http://www.zx81stuff.org.uk/
Great emulator here:
http://www.vavasour.ca/jeff/ts1000/library.html
To convert .P files to audio for Sinclair try "winTZX" at :
ftp://ftp.worldofspectrum.org/pub/sinclair/tools/pc/winTZX0.9a.exe
Composite video modification. Worked for me!
http://www.zx81.de/english/video_e.htm

Category:

Education

Tags:

• Repairing
• Keyboard
• Timex
• Uncle
• Clive
• Sinclair
• 1000
• ZX81
• vintage
• Computer
• cracked
• ribbon
• cable
• Keypad
• restore
• fix
• Basic

[madmax2069]

I wonder if replacing that stock ribbon cable with a old ribbon cable that connects to a ATA HDD would work.

[bamageddrain]

@madmax2069 I saw somewhere online where someone cut the ribbon like 1" from the keyboard end, unsoldered the connector from the board and plugged it in right up close to the keyboard there, then used old drive ribbon to rewire the connector to the board. That's an option I've considered before too but it would be a little scary having to unsolder that connector from the circuit board.

[conorferguson]

exactly the video i was looking for... and when i opened it up... it was just as you described.. so now i'm at the part where i'm trying to get the ribbons back in...it's very tricky. i think i need another pair of hands to help... thank you for uploading this.

[bamageddrain]

@conorferguson Another note: The first time I tried this I noticed that on the smaller of the 2 ribbons the connector doesn't exactly line up perfectly with the ribbons position. Just the way it was designed. It makes it try to angle in a little bit as it goes in. The shorter the cut the bigger the pulling. If there is ever a "next time" I might try splitting that ribbon to reduce the pulling.

Good luck!

[madmax2069]

@bamageddrain yeah it could give you more troubles, especially with older hardware.