Repairing ZX Spectrum +2A tape deck

On ZX Spectrum +2A I have a tape deck was not working. Well actually it was working, but games were not loading as it seemed like the signal was missing. I will not go into details of disassembling ZX Spectrum +2 as it is pretty obvious. You get access to PCB of tape dec right away, to turn it around You have to unscrew couple of screws and that is all. Without any deeper investigation after disassembly I decided to do couple of things right away: replace all electrolytic capacitors with new ones, replace HA17324 operation amplifier with LM324 But unfortunately and to my surprise, after this hassle nothing changed, still the same issue. Then I noticed that something wrong with the powering on the board and it seems like the ground was missing. After some further investigation, I have found that ground on the board was delivered by two bold that was holding the board, as the board was removed, there was no ground in one part of the board. And maybe due to oxidation or something like that ground initially was an issue. I have inserted back HA17324, added a jumper between grounds just to be sure…

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Repairing ZX Spectrum +2A, composite video mod

I have purchased ZX Spectrum +2A to my collection and as with +3 decided to add a composite video out. First what I did I made this RGB mod to get s-video out, by: 1. Removing the 12V from pin 1 by removing resistor R44 (should be the same for +2A, +2B and +3, and very close to the RGB connector). 2. Adding this circuit Also detached audio from video by removing C24 and shorting from R46 to R56: I got the video out and it seemed ok at first, but when doing self-tests the result was a washout picture: ZX Spectrum +2A/+3 Schematic: ZX Spectrum 128K video fixes and video cables: Some useful links: https://retrohax.net/zx-spectrum-128k-2-repairs/ https://spectrumforeveryone.com/technical/removing-blueyellow-ghosting-1282s-video-output/ https://www.youtube.com/watch?v=GMKGIP5Yuqs   https://sites.google.com/site/lost8bits/sk/sk-zx-spectrum/sk-datacoder-fix        

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ZX Spectrim 128 +3 composite video output and drive belt replacement

Did some work on ZX Spectrum 128 +3 I have. One thing was I wanted to make it work with small "TFT Color monitor" (for a car rear view). This monitor has a composite video input. First I tried using CSYNK and GND signals for a composite video input. You get the video but it was terrible quality. It seems that "The 128 ZX Spectrums including the +3 (and +2A, +2B) have audio sound modulated onto the video, which reduces the clarity of the composite signal that is available at the modulator input."(1). Then I found this document - "Video fixes and video cables for all ZX Spectrum 128K models". There is a chapter on Creating composite video-out on a +2A / +2B / +3: "Although the ZX Spectrum 128K heat sink model and the grey ZX Spectrum +2 have a composite video-out signal on pin 1 of the RGB connector, the ZX Spectrum +2A, +2B and +3 are missing this feature. Instead of the composite video signal they have a dangerous 12V on pin 1 that will seriously damage your TV or monitor! But you can add the composite video signal yourself, with the same fairly simple circuit as that…

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Some notes from The Spectrum Show

Some notes I made watching The Spectrum Show. New games: Antiquity Jones 2012 Paul Jenksinson More Tea Vicar 2012 Cronosoft Future Looter 2011 Timmy Alter Ego 2011 RetroSouls Genesis: Dawn of a new day 2010 RetroWorks Interesting old games: Glug Glug 1984 CRL Ninja Hamster 1987 CRL Worth remembering: Arcade Pac-Man emulator for ZX Spectrum Arcade game designer 2008 Chronosoft  

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Recommended retro ZX Spectrum related Youtube channel

If you are interested in retro computing, especially Sinclair ZX Spectrum computing, I highly recommend Paul Jenkinson The Spectrum Show if you haven't found it yet. It is very well made series with a nice structure: news of that era, software comparison, game reviews, new software reviews etc. Highly recommend. https://www.youtube.com/watch?v=UhIHy-pyMwo  

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Making ZX Spectrum edge connector

If You are a little bit into retro computing and would like to experiment with ZX Spectrum computer outputs or make some extension board for it for some prototyping, then you need ZX Spectrum edge connector ( if we talk about original ZX Spectrums ). It is easy to make one by Yourself, just buy some regular 28x2P 56P 2.54mm 0.1" edge connectors on ebay and saw off both ends of it so they could be used for ZX Spectrum, done. https://www.youtube.com/watch?v=ZMIq1yrzVTo

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Cleaning and repairing ZX Spectrum +3

Got a somewhat cheap ZX Spectrum +3 to my collection. It was marked as untested in eBay ( they usually are ), but I took the risk and bought as the price was ok.  On first test it powered up, the floppy disk was providing sound, TV could be tuned and startup menu appeared. First noticed that some of the keys ( lower part ) were not working. My guess would be that membrane will have to be replaced but anyway, disassembly will show. And it showed. As it more or less was obvious from outside inspection - inside was dirty as hell. Then, after some cleaning: I have no CF-2 floppy diskettes to test, so decided to plug in a tape recorder and test some software from and audio cassettes and the i noticed.. that audio jack was missing! It seems that it was just cut away! Found similar one in one my spare parts box and soldered that in. Also decided that as soldering iron is hot anyway why I would not just make a quick composite mod in the UHF box (using a capacitor). Did that, reassembled it, plugged it in and... yeah - no video.…

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Extending BASIC

Good article from Your Spectrum magazine (1984) regarding methods of extending ZX Spectrum BASIC.[googleapps domain="drive" dir="file/d/0B3YJXuFJXqAYLWZzeEQ5TTNsX1U/preview" query="" width="640" height="480" /]

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Interface 1bis file not found error

Purchased Interface 1 bis for the ZX Spectrum. There are plenty information about it and installing and preparing SD card on manufacturers site https://sites.google.com/site/interface1bis/ But I have encountered a problem - could not start it and was allways getting "file not found" error.Did all steps described in troubleshooting video https://www.youtube.com/watch?v=QYHhWQyVWAU Loaded OpSys from PC using LOAD command, program loads OK. But when I do NEW and then RUN I get "file not found" error. Solution I found was that I had to repeat all prepare SD card steps, but additionally had to add comparability with Windows 8 (and run as administrator off course) option (I was running Windows 10) to LDCSetup.exe and later to the 'Prepare new card' utility.So, In short - add Windows 8 compatibility to Interface 1 bis utilities.

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