Building the World's Newest Amstrad CPC 

I respected you before I saw this video but after seeing that you've taught your daughter to solder and you play MInecraft with her, I think you're freaking awesome.

Love that you got your daughter doing some hands on learning. Kids need more early introduction to skilled trades. Even if they never pursue it as a career, they will always have the knowledge.

So glad you got it going. And sorry you had to be the guinea pig tester! Thanks for your effort and patience and keep up the great work.

Teaching my daughter how to solder continues to be a highlight of our growing up, and she still talks about it. Well done!

AN easy way to find PCB shorts is to run a couple of amps through it and use either a thermal camera, or film of alcohol to look for hotspots.

As a woman in electronics tech I just want to tell you how much I love that you involve your daughter in your projects and teach her the trade. Thank you for your wonderful content and your great parenting. :)

in the 80's I had a summer job while at Uni fixing avionics boards for GEC, and one way we found shorts on PCB's was to connect a current limited supply to the traces in question, and use an accurate voltmeter to measure the voltage at various points. As you get closer to the short the voltage gets lower, as you get further away it goes up. If you use a low enough voltage you can often avoid activating semiconductor junctions and thus cut out that source of errors - I traced one fault using a quarter of a volt and a (very expensive!) accurate voltmeter. I suspect that nowadays a relatively cheap multimeter with decent probes would probably be stable enough to work. The very low voltage power supply might be more of a problem!

I’d love to see a post mortem on that transistor. Why you thought it was equivalent, how it wasn’t, and hopefully a new modern equivalent. Great video!

This took me back to 1984 when the CPC464 was my first computer. I was still using it and my second machine the CPC6128 on release, right up to 1995. It was here I bought my third computer a Packard Bell with Windows 95. I had a great collection of the cassette tape games, along with the not so Floppy, floppy discettes. The monitor to tv converter and digital clock, Primary and secondary disc drives, the Romantic Robot from STS and disc. I even had the Eprom boards for blowing my own chips. Though the best mod I ever did on my CPC6128 was to fit the 464 chip, piggy backing the 6128 chip with one pin bent outward from each chip. Then with a toggle switch wired to those pins that when thrown it connected to the pin hole on the PCB. This in turn when the switch was thrown one way or the other before start up, would then boot the Amstrad into either CPC464 or CPC 6128 mode. That gave me two Amstrads for the price of one. I can't remember now about the mod, but I am sure if you don't know it, someone out there will know how it was done. It is a neat little mod to do if you are interested in both Amstrad models. Going back to the cassette tapes, I had all the Amstrad Action magazines and cover tapes. After purchasing the Romantic Robot from STS, I ran the game Chips Challenge, pressed the Button on the RR and up popped the code. During the game each level had a 4 character code to by pass levels you all ready played and continued from the higher level if the correct code was inputted. After having about 12 or so levels completed, I looked for the codes in the lines of the game programme code lines. These where broken up into four blocks and each block equalled a letter of the code as 1st, 2nd, 3rd and 4th if spread sheeted into columns. I found them all and a few bonus levels too and wrote to Amstrag Action with the results and had them printed in the next available issue. For the life of me I can't remember the issue number, but I am sure there is a copy of the magazine out there somewhere. Sorry for the long comment (excuse my grammer etc), but I thought you and the other readers would be interested in reading my experience with my Amstrad CPC machines etc.

I cut traces normally with a sharp blade knife or scalpel, cutting at a slight inward angle from both sides, essentially cutting out a shallow V underneath the trace.

Just a couple of mistakes and an omission on a big board he hasn't yet tested? That's actually very impressive. Rob did a terrific job with that and kudos to you for building and testing it. Now Rob can get a perfect working replica board out there thanks to you.

That's sweet that your daughter helps you like that. My daughter helps me build guitar pedals that we sell but she's a teenager now so offering to play Minecraft wont cut it, they want cash. lol

i m a great fan of Amstrad CPC... my brain exploded watching this video! I want make a new Amstrad CPC in 2022! Marvelous!

A good way to remove unwanted traces is to use an X-Acto knife. The X-Acto knife works really well and looks really clean when you’re done. This looks like a fun project but finding the shorts on your own would’ve just driven you nuts, glad you found the shorts and were able to take care of them.

Problem with current fpga’s is that they are 3V3, so as well as the fpga, logic converter chips are also required. The low end Tang Nano and Lattice MachX02 can easily replicate the digital functions contained in the gate array chip for those 8-bit computers. So if I designed a replacement solution , it would be a small board containing a few chips to plug-in where the gate array chip goes.

Wonderful =D Nice fault diagnosis there on the VCC to ground, and with the CPU clock! Rob did a great job on that PCB re-creation!

I forgot to say this in my last post..... I've never used and Amstrad CPC but your video is so good that you've inspired me to one day build one. Thanks for this video!

Instead of scraping the track away with a screwdriver, you should have used a scalpel to slice through the unwanted track. Much quicker, more precise, and neater. A trick I learned from my years in the Air Force.

I am actually surprised that only 3 board errors were present from photo-copy/tracing the original board. At the same time, I'm also surprised that this was never tested, not even once, before shipping it. In my humble opinion that I greatly respect, the best replica of an Amstrad CPC (64K, 128K, with tape or with floppy) would be a modern redesign of the board, with as many quality of life features as possible, while still being "layout compatible" with original cases. I would not mind if it included a R-Pi-0 GPIO header to sandwich a Pi-0 on the board for WiFi, ROM-loading/dumping, etc., maybe even HDMI video and sound. This would be something like the ultimate sleeper Amstrad CPC fully upgraded and not emulated/FPGAtiated. Running SymbOS Z80 (in addition to original and modern software) on such a machine would be a treat.

Very cool Noel, and you have perfectly outsourced the soldering part to your compagnon :-D Great works!!!!

Maybe I'm weird... I like to solder IC sockets!. When you get a VCC - ground short it's time to get out the €4,000,000,000 precision resistance meter... No, I don't have one either. The picture-in-picture of the 'scope probe on the schematic is excellent... liked that a lot.

I LOVE these retro-forensics videos! And YES, using the original hardware is always the prefered way. Just like vintage cars, we don't put anything "modern" that will look out of place, unless we have to. That's the whole point, to keep it as close to the original as possible.

Just dropping a line to say a fair amount of this went over my head, but I couldn't stop watching. (The hardcore, old-tech-loving, nerd in me...) In fact. I'm halfway through my life and considering an engineering degree. The interesting things that happen when you figure out you are on the ASD spectrum super late in life, you stop giving ***ks about everyone else and what they think and go after what makes you happy. Watching these videos is among those things. :)

This is so encouraging to see. I dusted off my CPC664 this evening, cleaned it up and inspected it... I won't be risking plugging in the monitor until it's had a thorough recapping so I can't power it up... I need to sort out an alternative PSU and some kind of video lead in the meantime. I spent so many hours in front of it as a teenager and really loved the machine, I was involved in the fanzine scene running a small CPC fanzine for a period of time - we were featured once in Amstrad Action. I also have a dead CPC464 I picked up about 20 years ago which I know doesn't work but it's in great cosmetic condition and has the proper retro GT65 green screen monitor. Some of your diagnostics on this new board will surely help me to diagnose it and I'm really pleased it seems most components or alternatives can still be purchased (apart from the ULA obviously). I'll be certain to watch more of your vids and have subscribed -- thankyou for producing this content!

Excellent work. Rob is doing a great service, creating these beautiful boards. Getting a replacement board from Rob is my next step if I can't locate the broken trace or solder bridge on my C64.

I don't care the make or model of these old PCs. What I DO care about is that there is such a strong community bringing ALL these old PCs back. That means we all win in the vintage PC scene... That being said, I always wanted a CPC. Those things were just gorgeous.

15:40 at least with the C64, we have good replacements with GALs, but the CPC is a whole other story! So much of its logic was in what was almost a CPLD. (As a C64 kid, I'm obviously biased, but the CPCs were nice machines only held back by their clock speed. And I really appreciate the plus series.)

This was based on a board that I sent to Rob. I like to think of that board as Jango Fett and now there's all the clones.

Hi Noel, this is kind of a love letter comment to your channel. I am in awe. I am not really familiar with these devices and generally anything from their era but I've always been fascinated. I think you're by far (even though this could be personal opinion) the most interesting channel about this stuff. I absolutely love your personality, your editing, and your skillset. I hope to be able to learn something from how you run your channel. You're one of my inspirations, I don't think it means much right now, but maybe someday it will :) Absolutely loved this video. I was even a little sad when it ended.

Very nice teamwork between Noel and Rob! Great video, as always.

There is a technique for locating a short like the ones you had. Set your power supply to something like 1 volt, and set the current limit to maybe 100 mA. This will prevent damaging any traces on the board. Now apply 1V to wherever it would normally come from, either a voltage regulator if there was one, or a power connector. The voltage will drop down to a low value because of the current limit. Maybe 0.1V or less at the source. Now using the mV scale on your DMM, measure the voltage between VCC and Gnd at various points on the board. The voltage difference at points between the short and the power feed will be very small, but not 0 due to the trace resistance. It may only be a few mV at some points. As you get closer to the short, the voltage will drop. If you measure between VCC and Gnd on the "other side" of the short from the power feed, there will be no voltage, so that would also tell you that a short is between where you are measuring and the power feed.

Another great video from yourself and board from Rob. Definitely going to get one of these once it goes on sale. The 40007 version of the gate array always comes heatsinked from the factory in all the CPCs I've ever seen, so would likely be worth adding one to your board rather than risk another one dying prematurely.

The CPC464 was my first computer. My parents were toy retailers in the 80s with several big successful stores and good connections, and managed to get a fully functioning promotional unit towards the end of '83 - earlier than the official release date (it even had the full colour RGB screen, not the green screen or the TV module). It was supposed to be a demo model to go on display in their main store but it never made it there. They gave it to me as my birthday present that year and I've been glued to a computer ever since. 😂 Awesome to see that they can be built at home relatively easily now. I might have to give it a try!

17:49 not every hero wears a cape. That's why opensource projects are growing rapidluy - thanks to volunteers ^_^

The Harlequin, (a Spectrum 128K clone), uses off the shelf logic chips to replace the ULA. Larger modern RAM chips, a surface mount chip for the video and a PCB that fits into a rubber key case or a 48K+ case. It also has Svideo out. It was fun to build, but yes, all those IC sockets were the boring part of it.The only original IC I had to use was the AY chip.

That's awesome to see Rob making more of these boards available. I'm currently building up one of his C64 boards. The great thing about the C64 boards is that new cases are available too.

Always good to know people out there are making sure the legacy of some of these old machines are being kept alive. My guess is a CPLD would be more than enough to handle that Gate Array chip. Of course some of those single board computers might be an alternative using an adapter to pop into the socket. Nice troubleshooting also!

Noel, the issues you experienced with the board you showed in this video were actually fairly common back in the early days of computing. It's why many "retail-ready" production computers and electronics have bodge and patch wires, resistors and capacitors soldered in post assembly. I have a do use a razor blade to keep cuts more precise, but can't fault the use of a flat-head screw driver. Love your channel! Cheers!

Thank you for this video and for all your efforts. It makes me remember my beloved Amstrad CPC 6128. I also had the Sinclair ZX81 and Sinclair spectrum 48 ....the Vic 20...Commodore 64..Amiga......this was a fantastic era

My Daughter loves playing games on my 40 year old Speccy. She loves the retro aspect.

Really great job building and debugging this first revision board Noel! You have some seriously sharp troubleshooting skills sir!!! Thank you for sharing your voyage down "Amstrad Lane" with us Noel. Fred

Excellent video as ever! Great to see these boards exist, and if there are new 40007 coming, even better. I see this as a great repair item for a CPC that has had serious board damage, use the case and keyboard etc from that to save it from the rubbish bin!

This channel is a real inspiration for most of us. Your content, edition and explanations are on the best of RU-vid. Thanks, Noel, for these videos!!! Keep up the good work!!!

Noel, I really enjoy your channel. It's given this American a greater appreciation of the "other" 8-bit machines of the world that influenced the history of computing as much (or more, like the BBC Micro that eventually gave birth to ARM etc) than the stuff that was popular/invented in the US around the same time. 👍

Great job! I am an electronics diagnostician. I have found bridges on tracks, just like the ones you had. A very sharp craft knife or scalpel, lightly scoring the part to remove before teasing up the edges will look much better. I have used this method to modify boards. I recommend a good magnification device. It’s more important to take take and score lightly several times rather than deep score just once as the board and any interleaved foils can be damaged.

"And just like that, the board continues to assemble itself without my help." 🤣

Hi! There is a good way to save some time and alcohol while cleaning PCB after soldering done. Just use regular paper towel soaked with alcohol. Sure, towel will be destroyed, but paper will accumulate all the residues. Just use some brush to clean all the paper scraps.

Amazing video. And your Amstrad test code works perfectly with the new board too (it couldn't be any other way, but it works). Thank you Noel for another excellent video !!!

If I want to remove a piece of PCB track, I cut each end of the piece I want to remove with a sharp scalpel and then heat the copper track with a soldering iron and it lifts away quite nicely 🙂

This is wonderful. Also, this lovely replica board is based, i believe, off a RevA board i stripped from my original CPC, gave to a friend who in turn gave it to Rob. I'm pretty sure this is the case.

Me and my daughter also solder and play minecraft together. Seeing that really made me smile

the only time I ever met a celebrity was when I delivered pizza as a student, and delivered one to Simon Forrester, tech writer for Amstrad Action magazine and someone who had an entirely unsuspected influence on my young mind

From a guy who worked with circuit level repairs on Supercomputers: It's easier to break traces by using a very sharp utility or hobby knife, then either use the knife to lift a section of the trace, or once cut, use a blunt pick (like a dental pick) to gently widen the gap. It looks much better too. Even supercomputer engineers make design mistakes and boards have to be modified.

GENIAL ! Mon premier ordinateur, que de bons souvenirs. Merci. Thank you.

Great video!!! Having done the same thing for CoCo 2 and the CoCo 3 replica boards, I can totally relate to the snags you experienced. I'm currently in the process of searching for a handful of equivalent modern replacements for some diodes and transistors.

And again a 5 stars video. I enjoyed both the pcb design and the fixing process. And yes it would be great to understand what happenned with that transistor.

Another great video and content. Thanks !!! This is becoming my favorite youtube channel !!!!

Great video Noel.. always look forward to them.

Brilliant Noel! I really enjoyed the video.

Great vid - may I suggest the use of a scalpel to cut tracks rather than a screwdriver? It's more precise and reduces the risk of accidental track damage.

BOUT 10 years ago, at the dawn of the Mechanical Keyboard era, I was at Uni. I got my first £7000 grant / cheque and, while I've always been a frugal and intelligent gamer, never splurging on top end overpriced hardware but using my nogging to build in the perfect "sweet spot" over the years, I thought .... hell with it. I'm buying a nice keyboard. Read the reviews etc - settled on a Logitech G710. It was very expensive, £144 ... but it felt amazing, ridiculous build quality, and felt like and reminded me of my old Amstrad CPC machine. Still lives to this day and, while OOP for a long time, I managed to snag 2 brand new sealed german versions a few years back for £45 each from eBay. Swapped out the keycaps and I have two here, probably enough to last a lifetime, keeping the CPC464 vibe going on my desk.

Very skilled and entertaining. I enjoyed very much, and learned at the same time. Thanks !

Really nice adventure building this computer, thanks!!

Enjoyable episode... always love the troubleshooting.

This was fantastic to watch! Great job!

With a pretty helper like that who can resist building a CPC from scratch !!!

I love the daddy daughter thing,I love it when my little one wants to help ,they grow up to quickly

That wholesome Minecraft moment made my day :) hope you two have a great day too!

I thought that I loved my amstrad cpc... but your job,... that's really true love !!! (and technical and resolution capacity, of course) You're a monster dude

Really great video and awesome support from the creator 2 tiny issues is a really great sign hopefully that's all you can find

I had a CPC464 as my first computer. This video gave me major nostalgia

Great work. Good to see it's possible to increase the stock of actual hardware through a mixture of new and replica components 👍

Good catch on the shorts on that board. Thanks for the links. Now all we need is 3D printed Amstrad replica case plastics..

I went the first path with recreating an Apple //e board to learn more about circuits back in highschool years ago. My favorite machine of that era is the Apple IIGS, thankfully my Woz Edition I got in the late 90s loaded with the best expansions and accelerator of the time still works great. I fear when it breaks with the GS not exactly being very popular compared Macintoshes and //e's of the period. I have had to repair a //e titanium that had the GS upgrade kit installed but thankfully it was a simple fix.

Nice replica project! 👍 Great video and new board diagnostic!

This is where using a real pcb layout program comes in handy. DRC (Design rule checking) has saved many of designs

Great video! ... and great that there is a new board for the CPC464.

Nice. I have fond memories of using a CPC464 back in the day.

Really cool video!. Thanks

Great video. At last the cpc gets some love. Thank you.

That was fascinating to watch thank you so much

Superb Noel. Great video.

amazing video as usual! Thank you!

This is some hard core stuff right here well done sir

sooo cool... im gonna have to grab one of these boards, can you post a reminder when they are released please Noel... cool to hear about a 6128 board being worked on, i may even just wait for that, and drop my 464 bits into it...(with a 40007 mod or replacement CPLD/FPGA)

Another great video -- thank you!

Bravo, una pasada!!! Siempre se aprende viendo tus vídeos.

Very good job. From both of you.

Genius.. At last... Very well done.

My first computer was a CPC464 - good memories

rebuild with more memories more and more will be better

@Noel Great video to watch, I love being able to learn from watching your great explanations. My 1st comment disappeared for some reason (too wordy :D ) but I'm inspired to play with the 1983 1st gen CPC464 I have now and give it some love from your great videos. I'll grab one of these boards when available for sure.

Fantastic video and fantastic project by Rob. Love to see our special connections to history being preserved in a way that will never die. By the way, did you find a modern equivalent to the ztx312?

5:12 - too adorable! 10:20 totally unnecessary analogy...seriously...we got it, we're not that stupid 🙂

I have a hard time deciding if I want to build a cpc or a msx. As always wonderful video!

Many hundreds of hours playing Paperboy, Arkanoid, Thundercats, Batman and so many other games on all of the Amstrads we had.

Really liked this episode. I had the 464 and the 6128 back in the days. I learned assembler on these machines. Sadly I don't have the computers anymore but I do have some Compact Floppy Disks that I didn't throw away for the 6128. So... it would be cool to maybe "build" a 6128 myself.

Great Video.👍👍

Very nice. I will definitely get one of those when they come for sale!

Nice work.