Introduction
I’m a member of many Facebook groups dedicated to Amstrad computers, and in one of those groups called Amigos y Usuarios de Amstrad which I think means friends and users of Amstrad in Spanish, I spotted a post by a very nice guy called Juan Giovanni Ciller, and it caught my eye immediately. This is one of the most interesting things I’ve been involved with in the Amstrad scene in a while so I had to blog it. I hope you enjoy the story.
Basically he had purchased two different CPC 6128‘s over a period of time, months apart actually and he just happened to notice that the serial numbers were nearly identical, only 13 digits apart !!
Here’s a screenshot of that first post (in Spanish) with the translation below that.
and here is a closeup of the 2 CPC 6128 serial numbers,
Notice how both have a Version F sticker on the rear, and the text on the serial number sticker is in French. These CPC’s were manufactured in Korea.
What are the odds of that ! This was so interesting, as it could give us a look at how consistent (or not) the manufacture of these devices was back in the late 80’s.
I responded to the post and asked Juan to take more photos of the inside so we could clearly see (or hopefully see) some common traits of these 2 brothers. Juan was very obliging !
Here’s our initial conversation.
After that post, he modified his original post and showed more details of the two computers from the inside, how cool is that !
The motherboards
Here are the 2 CPC’s open, showing the motherboards.
This is such a cool photo, you can clearly see that they look nearly identical, maybe even the same person put them together, who knows. What we do know is they were definetly manufactured in the same factory as some of the parts are ‘in series’ meaning that they were pulled from a batch.
The Floppy disc drive motors
Juan very nicely posted more pictures of those similarities such as these Floppy disc Drive motors with a part number of MMA-6U2LEP, both manufactured on the 10th of July, 1986.
This means that when the assembler put these computers together, they pulled parts from a common source, which is confirmed by those exact same dates on the FDD motors.
The stepper motors
Next, we can see 2 more parts connected to the Floppy Disc Drives (FDD), I believe this is the Stepper Motor which adjusts the read/write head to move up and down the inserted floppy disc.
The only difference on these are the serial numbers, everything else is identical.
The motherboard serial numbers
Here we can see the 2 serial numbers on the motherboards themselves, obviously they need to be different, but we are hoping that they are also very similar.
and yes they are similar, the K is probably for a Korean factory. These motherboards were manufactured 62 units apart !
The keyboards
Below we can see the two serial numbers of the keyboards.
The date code is slightly different but everything else is the same !
Differences
However there are also some differences.
Next, we have a closeup of the date of manufacture of the plastic cases, these are not identical. Someone has written what looks like, and it might be the same person writing this, or not, i’m not a hand writing expert, from first glance it looks like different styles of numbers.
on them, and i’ve no idea what that signifies. There are date codes on the plastic, but they are hard to read.
From what I can make out the case on the left has the following date codes:
and the case on the right has
If someone out there knows what these numbers mean then let me know. I’m sure the 85/86 means it was around 1986and the others probably signify the month/day of manufacture.
The bottom CPC 6128 is missing the Amstrad 40010 Gate Array, and it has a different chip top right (NEC versus Zilog)
I noticed in his Facebook post that ‘one works’ which is most likely the one that still has the 40010 Gate Array chip inside, a previous owner may have removed the chip on the other one, I’ll ask him to confirm and update this post once I know more.
We can also see that whoever marked these parts did so with different coloured pens. What does that mean ? we don’t know. Could it be from the person who assembled the CPC or infact, from the person who assembled the motherboard, and were these done in different places, we do not know.
Aside from the pen colour, the parts below differ based on
If anyone knows what this means, let me know.
More info (from the videos)
I chatted with Juan on Facebook chat and luckily he understood English, and not only that he was very willing to tell me more. I asked him could he video the twin CPC’s and he sent me three videos explaining the story and showing them in detail.
In a nutshell here’s what happened based on Juan’s own words in the videos.
The first one was bought early 2022, from Ebay, paid about 100 euro, belt in the disc drive was gone but the rest is fine, a bit dirty but OK otherwise
The second one was bought in December 2022, at a flea market in Toulouse, France. He was surprised, to see it there so he bought it ! He cleaned this one up as it was very very dirty and some of the keys were stuck.
‘I have to save it’.
This one cost him 50 Euro.
Both of these CPC’s are French versions with the Azerty keyboard. I’m not sure why Juan (who I assume is Spanish) wanted French versions of the CPC 6128, I have yet to get that clarified.
A couple of weeks ago he tried to repair them. And it was at this point he realised that the serial numbers were nearly identical. What are the odds of that !
In the below photo we can see a clip from the first video that Juan made for me describing his story purchasing the 2 CPC 6128’s. The keyboards look different in colour, one is discolored and the case is scratched, but these two CPC’s are twins !
so what do you think of this story ? are these CPC’s from 1986 really twins, were they made in the same factory and on the same day, let us know!
cheers
niall (and Juan)
Next we need to find out what is wrong with Line 652 – Undefined Symbol. To speed that up, let’s use CTRL+G to go to the line number 652.
