How bad was the wobble on the zx81

General Chit Chat about Sinclair Computers and their Clones
User avatar
1024MAK
Posts: 2195
Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: How bad was the wobble on the zx81

Post by 1024MAK » Wed Nov 07, 2018 11:44 pm

It should also be noted that the ribbon cable system for the ZX Spectrum did not work as well as you may have expected. After all, look at how many wires make up such a link, then consider that they are all glued together, hence they are rather stiff. So no real improvement...

What is actually needed, is a connector that is designed to be a proper mechanical linkage. Card edge-connectors are actually intended to just be used for electrical connections in a card frame system, where PCB runners and other mechanical fixings are used. In such a system, card edge-connectors are much more reliable.

Mark

User avatar
gammaray
Posts: 562
Joined: Sun Apr 17, 2016 2:44 am
Location: Texas

Re: How bad was the wobble on the zx81

Post by gammaray » Thu Nov 08, 2018 12:12 am

There was also a vaccu-formed plastic tray where the cables routed underneath and the tape deck, zed and rampack sat in pockets with a inclined plateau for the TV to sit on. *Perfectly fitted so nothing would move.

C
5-TS1000,UK ZX81<-Sheelagh, US ZX81, 2-TS1500/KDLX , 3-TS2040 printer, 2-TS2020 cassette decks, ZXPAND+AY, ZeddyNET, ZXBlast, UDG, ZX8CCB, AERCO, BUILDS/REPAIRS ZX Spectrum, ZX80 Minstrel, ZXMAX48 v1 v2, 2-TS-2068, ROM, 16kRAM

brozier
Posts: 7
Joined: Sat Jun 24, 2017 6:56 pm

Re: How bad was the wobble on the zx81

Post by brozier » Thu Nov 08, 2018 2:00 pm

Crayon21 wrote:
Tue Nov 06, 2018 11:19 pm
I've heard a lot about the wobbling issue with the ZX81. how bad was it? did it really wipe out everything?
It was very frustrating, I made a little metal bracket that clamped the Sinclair Rampack to the main case - using the original screw holes. Helped a lot.... :D

Julia

Moggy
Posts: 1709
Joined: Wed Jun 18, 2008 2:00 pm

Re: How bad was the wobble on the zx81

Post by Moggy » Thu Nov 08, 2018 6:49 pm

brozier wrote:
Thu Nov 08, 2018 2:00 pm
Crayon21 wrote:
Tue Nov 06, 2018 11:19 pm
I've heard a lot about the wobbling issue with the ZX81. how bad was it? did it really wipe out everything?
It was very frustrating, I made a little metal bracket that clamped the Sinclair Rampack to the main case - using the original screw holes. Helped a lot.... :D

Julia
Hells teeth! I have a ton of those little "L" shaped brackets how come I never thought of this!!?

DUH!! :oops: :oops:

swensont
Posts: 58
Joined: Tue Jan 18, 2011 4:55 am
Location: SF Bay Area

Re: How bad was the wobble on the zx81

Post by swensont » Sat Nov 17, 2018 1:18 am

I faced two issues when I got my ZX81 in Nov. of 81.

1. Kept over heating and crashing

I learn not to use the ZX81 on a shag carpet. Once I put it on a desk or such, it was fine.

2. Moving the ZX81 with the 16K pack would cause a crash

When the ZX81 was picked up, the 16K pack was not secure enough to not move. It moved slightly which caused the top edge connectors to disengage from the ZX81 external connector.

My solution was to use duct tape to tape the ZX81 and the memory to a small piece of peg board. Now that both were secured to the board, I could pick up the ZX81 with no issue. The ZX81 and memory did not move in relation to each other. It was a big ugly, but very effective.

User avatar
Ed in SoDak
Posts: 17
Joined: Thu Jul 24, 2014 1:03 am

Re: How bad was the wobble on the zx81

Post by Ed in SoDak » Sun Jan 06, 2019 5:17 am

Most everyone enjoyed cussed at the same quirks. My first quick answer was to solder the outer RAMpack terminals to the TS1000 connector. Later, I solved the poor loading, heat, RAM wobble and keyboard problems with a little hacker upgrade. A surplus TI99 keyboard in an open bottom plywood case with soldered RAM and board mounted within and a recessed power switch plus loading meter on top.

The TI keyboard required a lot of cut traces and added wires to adapt it to the Timex, but everything else was pretty simple soldering of a few wires connecting the switch, power jack and meter. I'd program in FAST mode and could enter lines as quick as I could type. It would run for hours without a single crash, even when moving it around a lot. Its beauty was in function, not looks! :lol:
-Ed
Attachments
EDO_4460.JPG
EDO_4459.JPG

Post Reply