Closed ZX Spectrum+ Keyboard repair

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cheezmonkey

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Hello,
I have here a lovely ZX Spectrum+ with a load of peripherals (2 microdrives + interface, joystick interface, printer interface, more) which my friend has asked me to look at for him as he doesn't have a TV which he can connect it to! Delighted at the opportunity to test this for him I picked it all up, hooked it up and tragically the keyboard is not what it once was. At first most of the keys worked, except enter, and a column up the middle of the keyboard. Maybe some of the shift keys too, not sure. Anyway, this means I cannot test any of the cool peripherals for him. He was keen to see what works and what doesn't, so I agreed to take a look inside for him and see if there was anything obvious (such as one of the KB ribbons being partly dislodged or something) - the slimmer of the two ribbons looked to be disturbed, so i gave it a gentle tug to remove it from the socket and it seems either I or the previous fiddler may have broken one of the tracks on that ribbon... Is there anyone out there willing to undertake the job of getting this lovely little unit back to health? My skills are quite limited and my time moreso, I am, of course, willing to pay for such a service.

Thanks for looking!
 
A bit more on this.. as the broken track was toward the end of the ribbon, I cut it at the split. I had to remove a little of the shielding too, but I'm sure that's ok... I'm now back where I started with the same cluster of central keys and a few outlying ones not working, still including enter, so I still can't do much. I've seen replacement keyboard membranes are being manufactured by third parties, so I'm going to get one ordered up. I'll try and fit it myself, but if I let the magic smoke out, I'd still be interested in finding someone more qualified who isn't just bumbling around with a failed electronics GCSE...
 
If you feel you are nervous to repair this then I would be happy to carry out the work for you.
I would also recommend we convert the RCA RF connector to Composite a Video which allows easier connection to modern TV”s and a better picture.

:)
 
If you feel you are nervous to repair this then I would be happy to carry out the work for you.
I would also recommend we convert the RCA RF connector to Composite a Video which allows easier connection to modern TV”s and a better picture.

:)

That's very kind of you, thanks. The new membrane is in the mail so I should have it in the next few days. I've read a few guides and I'm not completely hopeless, so I'm happy to try it out once - it's when this doesn't work that I'll be stuck :)

As for the composite mod, I looked very quickly into that yesterday as the crappy little 14" CRT TV I've hung on to just for things like this is definitely on it's last legs and it doesn't look too big a deal, but sadly neither my eyes nor my hands are what they once were and I have resolved to not operate a soldering iron in anger again... So another thing I may take you up on there. I did have a question which was not immediately answerable last night though... If that mod is done, where does the sound go? I should mention that I haven't had a working Speccy since I was a teenager, so it may be that the sound always came from the internal speaker and I just don't remember, but I did wonder about this mod and sound...
 
I am in East Sussex too, if you PM me your whereabouts I can help if you are close enough.

Failing that I can highly recommend Bas (TheCorfiot) :)



PS. the sound will always come out from the Spectrum internal buzzer.
 
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There are two way's doing a composite mod by using a:
1. capacitor
2. transistor
both methods are very easy to do.
If that mod is done, where does the sound go? I should mention that I haven't had a working Speccy since I was a teenager, so it may be that the sound always came from the internal speaker and I just don't remember, but I did wonder about this mod and sound...
I am using a usual AV lead that was modded, (one RCA plug was removed and a mono jack was added instread). i recommend this composite mod as RF output is very crappy.. Just check Youtube - there is A LOT of videos explaining how to do it:
https://www.youtube.com/watch?v=OnB2XgGsMgw
for example

About keyboard membrane - it's dead easy to replace it, just remember - on the Spectrum+ key membrane has 3 layers (one more as a regular Speccy, because of additional keys), same here - just watch some Youtube vids if You're in doubt:
https://www.youtube.com/watch?v=O61Yy00GHEc&t=746s

About Microdrives:
these are crap, to be honest, please do not rely on them, You will not be able to use them daily anyway, as these just falling apart. If You have an Interface II - You can use cheap programmable cartridges (building Your own, or by ordering these on Amibay from me)
https://www.amibay.com/showthread.php?93048-ZX-Spectrum-Interface-2-programmable-cartridge-10-in-1
Another useful hardware for daily use is divIDE (divMMC)
Also MGT +D Disk interface is very good (building and testing clone of it currently )
 
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You guys are all freaking amazing. Incredibly, I've managed to replace the membrane without breaking anything (although I did have to have a second go because semi-colon wouldn't work first time.)

I'll talk to my friend about the composite mod, this is not my Speccy, I'm just assessing and repairing if for him. He's ultimately going to sell it when I've finished with it (probably to me, though he doesn't realise this)
Thank you all for your help with this so far. I'm going to close this thread and start a new one about how I'm too stupid to make the Speccy format my one microdrive tape I have here...
 
Just a quick followup.... As predicted, I did buy the Spectrum+ from my friend. You guys have inspired me (as you do, every time I come here) to be bold. I had in a dusty old box my own ZX Spectrum (rubber feller, not the +) which had been left setup in my parents' crappy, unconverted loft, for about twenty years. I know, it's criminal. Anyway, I'd rescued this a couple of years ago and consigned it to the box for looking at another day. Yesterday was that day. I hooked it all up and amazingly, it still "worked." By that, I mean it put a picture out to the TV. The fact that it was rolling around and threatening to induce a seizure aside, I could see that it was working. Great. Lets test the keys.... oh hey look, 5,6,t,y,g,h,b,n all busted. Still, Sym shift, J and P all work, so again, limited testing is possible.

I'd been to my local Lidl at the weekend and by some twist of fate, they were doing a good deal on a soldering iron setup, so I'd picked that up, considering it fate. I decided this morning to jump in feet first and have a go at the RF mod on the crappy unit and..... by jove it worked! Not wanting to push my luck, I considered swapping out the board into the nicer unit, but I had the good sense to check that it actually worked properly first... Sadly, I don't think the EAR socket works anymore... It doesn't have a firm grip on the plug (its not loose, it engages, but it feels quite soft) and the unit doesn't seem to "hear" any input there. Boo..... Oh well. Guess I'm going for a second RF mod when I'm feeling bold again.

Thank you all for inspiring me!
 
Well that was easier than I expected, thanks DJ. That works now. Great. I also did the RF mod on the nicer ZX so yeah. A good few days all in. Hopefully the tape player I ordered on otherbay turns up today so I can test some of the boxes and boxes of tapes I've got here! Although, I must admit PlayZX on the Android is doing a fantastic job of being a tape player! If you've never tried it, I'd recommend giving it a go.
 
Well that was easier than I expected, thanks DJ. That works now. Great. I also did the RF mod on the nicer ZX so yeah. A good few days all in. Hopefully the tape player I ordered on otherbay turns up today so I can test some of the boxes and boxes of tapes I've got here! Although, I must admit PlayZX on the Android is doing a fantastic job of being a tape player! If you've never tried it, I'd recommend giving it a go.
well, last thing remain to improove Your speccy - is heat reduction. i recommend to apply a heatsink on ULA on Spectrum+ as it gets very hot and may fail soon. Unfortunately it can't be done on rubber key spectrums as case dimensions are very limited. What can be done - is to remove standard voltage regulator (as it produces a lot of heat, and replace it with a moderen dc-dc converter
 
Well that was easier than I expected, thanks DJ. That works now. Great. I also did the RF mod on the nicer ZX so yeah. A good few days all in. Hopefully the tape player I ordered on otherbay turns up today so I can test some of the boxes and boxes of tapes I've got here! Although, I must admit PlayZX on the Android is doing a fantastic job of being a tape player! If you've never tried it, I'd recommend giving it a go.
well, last thing remain to improove Your speccy - is heat reduction. i recommend to apply a heatsink on ULA on Spectrum+ as it gets very hot and may fail soon. Unfortunately it can't be done on rubber key spectrums as case dimensions are very limited. What can be done - is to remove standard voltage regulator (as it produces a lot of heat, and replace it with a moderen dc-dc converter

Would these do? I know the ULA is much bigger (these are 1x1cm) But maybe i could stick a few on there?
DSC_0027.JPG
 
Would these do? I know the ULA is much bigger (these are 1x1cm) But maybe i could stick a few on there?
View attachment 131498
it's a bit hard to estimate correct size by looking on the picture. Just try to stick one in the middle, if You are able to close housing properly - just add another two.
will make a photo of the heatsinks i use @ weekend.
 
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