ZX Spectrum 128 "Toastrack" Repair and Restoration
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- čas přidán 6. 08. 2024
- Support Noel's Retro Lab on Patreon: / noelsretrolab
We unbox a Sinclair ZX Spectrum 128K "Toastrack" Investronica edition. The Spectrum wasn't working so we diagnose it and track it down to bad CPU clock generated by a faulty ULA. Then we do a full cleaning (including a particularly nasty edge connector) and restoration and leave it as good as new.
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Don't understand why you don't get more views. You provide so much information during your restorations.
Thank you! I haven't been doing this for too long, so the channel is still growing. Hopefully more people will think like you 😀
He needs to do a "HEY WHATS HAPPENING GUYS!" thing at the start of every video.. Then constant begging to subscribe, and "hit the bell"... That's what all the other youtubers do.. works for them (sigh).
OMG a chip that says "TEA 2000" on it. At the time that would have been tea in the future!
Hi, Noel, greetings from Brazil. Back in the 80's i had two ZX-Spectrum brazilian clones models: TK90x and TK95 (manufactured by Microdigital). TK90x was my first microcomputer.
All your videos are very good, to be honest, one of the best repair videos. I have learned a lot about repairs.
And your english language is very easy to understand, the way you speech is very clear for people who are not very fluent in english.
Thanks for retro computer support!
Hi Noel! Hello from Northern Ireland.
Great job on the 128k! I have restored some classic Apple compact Macs and pizza case Macs. It’s a very satisfying feeling when you are able to bring back to life something that was not functioning correctly.
You need more subscribers and more views!
This warms my heart. Recently a friend of mine restored my Issue 6U toast rack that had a similar problem - at some point there was a failure that took out the Z80, the ULA and even the RAM chips. Somebody managed to repair it back then but it wasn't a particularly clean job. I guess that's life. But now it looks great just like yours.
Yeah, sometimes plugging in a 9V power supply with the wrong polarity can cause catastrophic failures like that. But that's the good thing about the Spectrum: they can all be fixed one way or another!
Just found your channel, loving thing so far. I really like how you show pics of the chips and you showing the miltimetre on each pin you are testing. Keep up the good work!
Thanks! Much appreciated.
Great restoration! Congrats Noel 👌
Thank you very much!
very cool, nice work on getting it working and good tips on the cleaning/protection.
Great restoration. It looks fantastic.
Perfect work! Helpful restoration assistance.
Great as always!
That interface you got with it looks like the Datel/Genius mouse interface.
As you look at it from the front of the Speccy, the left port is Kempston joystick (IN 31) and the right port is the mouse (IN 64479 up/down (X) IN 65503 left/right (Y) IN 64223 buttons (B)).
If you get a result of 0 from X or Y and 255 from B when you plug it in then it works.
I'm trying to write a point and click adventure with digitised photos for mine. I've also got a DivMMC Pro ONE with pass though edge connector so I can store load of pictures on that for the game. Sorry for rambling on.
Brings back my memories of electronic engineering.
Another good job!
Estupendo video!
Awesome I think I might put a new dc/dc convertor in mine. I highly recommend getting a divMMC Future SD card reader for maximum fun. Although the HDMI output looks great too as it has a thru port.
I like your vids so much that I don't even mind the "zee 80" thing. ;)
Zilog is an American company, so "Zee 80" would be correct.
Outstanding dood.
Great Vid!
Thanks!
@@NoelsRetroLab You are welcome. Very clever!!
128k ??? let me get this right ONE HUDNRED AND TWENTY EIGHT K ??? feck off !!! back then that was what we said when someone was talking crazy big memory !!!
Sinclair managed to make some of the STILL most appealing (if not reliable ) home computers ever , these days they are all much of a muchness but the thought and genius of sir Clive was written larger on these products we should be more proud of him in Britain then just for his failure of an electric car , his hifi was pretty good as well i just got myself a Sinclair system 2000 amp and it was serviced and it has such a sweet sound for my turn table and rogers speakers
Huh! one day I will get one of those beautiful engineering machines :)
They are truly beautiful! My favorite Spectrum model!
Ooh a speccy 128, blimey, they were rare as hens teeth at the time!
Would've liked to see you show us the extra keywords the Spanish 128 Speccy has. EDIT, DELETE, RENUM, and WIDTH. There's precious little about these variants of the Speccy on the net.
Investronica was the spanish distributor of Sinclair items...
Love your videos! One of the most beautiful computers I have ever seen. Whoever decided the port for connecting the numerical keypad should be on the front of the case should be put in design prison though.
As I remember it, they were partly sold on the idea that the keypad could also be used as a console type game controller. But I didn’t have one, they were an optional extra when I bought my 128k, and cost a ridiculous amount of money.. (not that I didn’t want one anyway just.. well.. because.. 😊)
Very interesting channel. I found a zx spectrum +2 on a trash some time ago (I know I shouldn't take it, but it seemed in perfect condition), but it was without cables/caset. What would be the easiest and cheaper way to test that it works? I opened once, and it had no corrosion or dirt.
Hi!, really enjoying your retro review videos :-). I had the 128k back in the 80s when they were first in shops. Couple of interesting questions for you, on this Spanish version you have, there's no menu, it boots straight into 128 mode, how to get 48k mode? If I remember right, was there not a command to do this? Finally, it would be curious to try the old ula chip with the diagnostic cart to see if it does anything at all. All these modern devices thesedays, pity we didn't have them back then;-)
Nice work! Aren't you tempted to keep the old ULA and inject the output clock with a signal generator to see if is the only ULA function missing?
Not a very well defined square wave on the clock signal. Is the probe compensated correctly?
Hi. Great video. I liked the look of that ROM cartridge with diagnostics. Could you provide a link to where I might purchase this item? Many thanks.
It's the ZX Dandanator. You can buy it here to just search for it on Ebay or retro forums: hobbyretro.com/retro/dandanator-zx Highly recommended for stuff like that!
Great video! What component supposed to be mounted in the large white circle on the main board by the edge connector?
Not sure. I think the UK version has it installed actually. Maybe some kind of coil?
Toroid. It's only mounted on issues 6K (Korean) and 6U (United Kingdom) though and even then there are some PCBs that don't have it. It's supposed to filter noise caused by the power supply.
I've got a toastrack , supposed of been recapped , the video output is dark, have bought a another 128 and its bright and perfect pic, anyone got ideas what might need replacing on the new one, could it be the replaced caps are wrong.cheers
I doubt that's it. Check that the TEA2000 has about 12V in pin 11. If it has significantly less, it could make everything darker. If so it probably means that TR4 and/or TR5 need replacing (or, it's true, one of the capacitors involved in generating the 12V line could be incorrect).
21:40. Wow, what is this device that loads the TAP files from the SD card?
Found it, it's divMMC.
When using the bench PSU it's better to enable the OVP and OCP before powering up the board with unknown problems. Even 1A can do a lot of damage if the power is not cut quickly enough.
They're already enabled by default (those are the numbers showing before I turn it on). I figured I need at least 1A because a healthy system needs around 0.8A. So I can't go much lower than that. Or do you mean something else?
@@NoelsRetroLab According to the user manual (static.eleshop.nl/mage/media/downloads/korad_KA3005D-2S_user_manual.pdf) the light for the OCP should be on when the protection is enabled.
@@alexwierzbowsky You're right! I was mixing my terms. I thought you meant that it was limiting the current, but the OCP actually shuts it down if the limit is exceeded, right? You're totally right. I should be using that but never got in the habit of doing it. I'll definitely do that in the future.
Hi, my name is Jose, I have an Amstrad 464 and the plastic base of the monitor has white spots because I sanded it with sandpaper back in the day.
with liquid polish and after many months I have managed to recover the color in some areas.
Can I restore the plastic case of the monitor and remove those stains with something effective and fast?
rom in spanish!! nice
Hold on, you just happened to have a replacement ULA from a +2a with the same date code? Bit of an odd coincidence that, editing error?
No, no editing error! That's the ULA I had. I didn't even notice the data code until you mentioned it.
At 21:31 there is that interface at the back... what is it please? I'm sure it is an SD Loader... Any info where to get one? thanks. Liked and subbed...
Hi Chris! That interface is a divMMC, specifically a divMMC Future from thefuturewas8bit. Fantastic interface to load games! That and the Dandanator are my go-to expansions.
@@NoelsRetroLab Thanks for your prompt reply... I have something similar ... I just have find it amongst all my stuff (upgrading tv/computer room... **sigh**)... love your channel.
Have a question? what do you do with the fixed ones?
They usually go in my collection, or, if I already have them, I used to sell them. These days I get more donations or loans, so I usually just return them to their owners.
@@NoelsRetroLab Thanks for reply. Nice to hear that. Keep going. I like your videos and your passion on your fixes. Regards from Costa Rica!!! Did you have a video sharing your collection?
is it dangerous to connect a test cartridge to an unknown faulty spectrum?
I suppose a really bad ZX Spectrum could damage the cartridge, but that has never happened to me. A dedicated test cartridge could have some extra protections, but I don't think this one does as its main goal is to load games, not be a test cartridge. Still, it's sturdy enough that I've never had a problem.
@@NoelsRetroLab ty for answering me
Shouldn't the ULA be heat sinked? I thought it got kinda hot.
I don't think it gets very hot. I'm not in the habit of doing that, but it's one of those things that never hurts. But it's not like the C64 that you really should do it. Most of the heat comes from the voltage regulator, so changing that one for a modern one is the most bang for the buck.
By the way, one can find M.2 drive heat sinks that fit almost perfectly. But as Noel says, using a modern voltage regulator such as Traco TSR 2-2450 reduces heat significantly. It can be mounted in a non-invasive way, even double-sided tape is enough to fit one.
What version of the zx spectrum consoles would you say is the best? Thanks. Great videos.
It depends on your goals. I love the 128K Toastrack for the power of the machine (RAM and AY sound) and the looks. And it was the last true Sinclair. If not, I'd go with the +2 gray, but it's the one that looks the worst (IMO). In the end I ended up with almost one of each type 😃
I'm pretty sure the red paint was actual nail polish.
Paint not conducting? No shit!
serviced and gott ripped in process ;) 4 x 93 is not 372 , i pitty the service with broken calculators ;) :P
That would have been really funny, except that 4 x 93 *is* 372. Either that or my calculator is also broken :-)
20E10FA13 - google to help. Four diodes.
Zed 80
0:30 to 0:40
You doing it on purpose!