AMSTRAD CPC resurrections

Sounds like a Resident Evil naming, however, it's not.  Basically, I purchased a CPC 464 with the built in tape-player listed on eBay as 'untested' and the when it arrived, well, it was rattling... The packaging was great, cannot fault the seller, they sold the machine as-is & I was buying it as-is.

After unpacking, it was clear that the tape-player was no good, there were bits of plastic & metal rolling around inside.  I did what you'd expect, I unscrewed everything, took it all apart and did some retro archaeology.  The machine wouldn't power on.  No surprise there, it was listed as untested.

I got my probes out and started to have a fiddle around.  So...power was getting to the main board, however, it is the cassette tape that controls the power switch and connects to the main board and gets the machine working.  The switch was duff.  Tested it and it didn't matter where the switch was, no electricity passing through it.  Maybe I can just bypass it?... tried that... nope.

Moved further along the chain... and the circuit board for the tape-deck proved to be the culprit, now this is where my level of probing stopped.  I don't have the equipment or know-how to be testing capacitors, transistors and all those other funky things on that circuit board.  What I could figure out though was that the cable that connects the tape-player to the main board was a simple set of about 8 wires.  I should only need a couple of those to get the machine to work?

So, out came the snippers and I chopped out the tape-deck.  Well, I did put it back in later for aesthetic purposes, but I will look later on to remove it completely and potentially place a 5" LCD screen in the place of the tape-unit itself.  we'll see.

I was then left with some wires and some simple "testing".  I eventually figured out (wasn't hard to look on the reverse of the board to see where +ve was connected to and where -ve was), then it was just a case of smashing cables together.  Okay, so I found that I could get a BASIC screen output - awesome, that proves the machine works okay. 

Then I found by shorting 2 other wires, which I believe would have been connected to the earlier broken switch, they turn the machine on/off - this is pure guess work - I fitted a small [reset] switch that I had going spare and it seemed to do just that, it would turn off and turn on the machine.  

Now, I might be doing something really bad there internally, I don't know, but it works.  Why am I skeptical?  Well, when powered by the CTM 664 official Amstrad monitor when I do this is turns off but doesn't turn back on again - however if I'm connected to the external TV via SCART cable and external modern PSU it works as expected, it does a reset.  I'm sticking with the win here.

So, after a wash of everything in the sink a good scrub to get rid of 40 years of gunk, I put everything back together and tested the keyboard - yep, all the keys work as they should.  I now have a fully functioning CPC 464 that works as it should.  Albeit minus the tape-deck.  However, with the modern day modifications being made, such as the DDI-5 I can just add a digital disc-drive that runs from a microSD card to load software from, so there is no real need for a physical tape-drive.

I would call that a success - a non-working CPC 464 and a very early model at that, is revived and brought back as a bit of a zombie - but it should be good to go for quite some time.  I placed the reset switch on the back of the machine and over by the printer connection, as I didn't want to mess around with the original on/off switch hole.

This then got me thinking....

I have had on my work/work office wall a piece of "object d'art", basically an Amstrad motherboard, as I have no found out a 6128 motherboard.

I also found a keyboard in the loft for a 6128, just the keyboard in the top half of a case - this is what started this journey off a few weeks back!

I then wondered, is that 6128 motherboard any good?  Would it power up?

Out with the probes again... and well, yes, it was getting the 5v power in various places on the board.  Oh hang on, the 6128 had a 12v cable that was required to power the 3" disc drive, what about that?  Well.. this particular motherboard didn't have the cable / connector for the disc drive, it had been completely ripped off / removed (I vaguely recall, that might actually have been by me back in around 2006-ish when these things were lots & plentiful, there must have been some issue with the machine that caused me to hack it up).  After a bit of fiddling around I concluded that like the CPC 464 earlier, if power was getting to the board and it was not "turning on", then there must be...

Oh there it is - a 2-pin switch that just needed shorting.  We now have the blue screen and yellow text on the lovely SCART TV screen.  Now... I wonder.. does that keyboard still work?

Plugged in, tested all the keys... yep, it all works!

I now have a zombie-6128 that has absolutely no disc-drive mechanics, actually no bottom-end of the casing, but it is, like the CPC 464 above, "alive-ish" and just needs a digital disc-drive mechanism to bring it to life... OR, if I were feeling like it I could get a broken internal 3" disc drive, fix it and then solder a new cable to the motherboard and it'd be good as new-ish... although I'm also liking the idea of not having the drive there are all and maybe having a small LCD screen that lives in the hole and when powered on it works like the car radio systems where the touch screen "comes out" and flips up, that would make for an awesome modification...  hmm....

I just need to fit a proper switch (I'll have one in the work/work office room someplace) and then fit that into the keyboard top casing so that blue/black wire isn't just hanging out on it's own.

Again, another mission success.

Right, time to measure up the bottom casing and see if I can get some acrylic plastic or something that I can screw that mother board to, so it doesn't short out on the metal of the bottom of the keyboard casing and then look to put it together and make a real machine.  I wonder if I should make it see-through? that would be quite novel.