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Good morning guys, welcome back to the ValorosoIT channel, the channel dedicated to vintage computers and electronics. Sorry, huh... I'm driving. Lately I have a little less time to make videos, so I decided to make some to stay in touch even in the car, on the short commute I have between work.
And today I wanted to talk about the donation that Vittorio had made to me, which was made up of quite a few objects. I told you I would let you know if these things worked or not, what was right, what was wrong.
Back then, the donation consisted of a Commodore 1702 monitor with its manual. After that there were two Commodore 64s, one of which was original boxed, with the power supply and box in excellent condition. So both the cartons and the styrofoams were in excellent condition.
The other Commodore 64, with its power supply, was boxless and has a modified kernel. In fact, it has a switch behind it that allows you to switch between the original kernal and the modified one.
Then we had two Commodore 1541 floppy disk drives, one of which was boxed, but without the cardboard, just with the polystyrenes. Anyway, a datassette for the boxed Commodore 64.
Then, relating to IBMs, we have the IBM 8513 12-inch color monitor and the IBM 8530 computer with an Intel 286 processor and also with a 287 math processor.
Well, this was more or less the list. I hope I haven't forgotten anything about the things Vittorio gave me, and I thank him very much, because it is truly an incredible donation, very very rich.
So, I've already tried everything. You have already seen some things, I published them on the channel, and the first thing I fixed was definitely the Commodore 1702 monitor.
So, I was looking for an original Commodore CRT monitor, I'd been looking for one for a while, but on eBay they all have absurd prices: there's even talk of 200, 300 euros for a working monitor in good condition.
This one, which was given to me, was really appreciated. When it arrived it was very dirty, and I didn't know exactly if it worked. In fact it also had the plug which was... eh... very bad.
So, I tried it quickly, I saw that it turned on, it worked. So I disassembled it all, I checked everything carefully, I saw that the capacitors were fine, I cleaned all the boards well.
I also actually dismantled the cathode ray tube from the plastic container, right into pieces. I cleaned them all almost obsessively, so now I have a brand new original Commodore 1702 monitor, it works perfectly and is in like new aesthetic condition. Maybe it has a couple of scratches, eh, but nothing special.
Um, I'm really happy about this.
And the Commodore 64, the one in the box, and therefore with the original cardboard and polystyrenes, doesn't work: it gives a black screen.
I've already tried turning it on two or three times, you never know that maybe there's a bit of oxide inside the switch, but nothing... it just seems dead.
So I didn't start looking at it more carefully, because I already have a few Commodore 64s working, in the various versions: I have the C version, the G version, the big 64... in short, I have a few already working.
So I'll keep this one quiet for the moment, waiting to have more time to look at it.
Instead, the Commodore 64, the one with the modified kernal, didn't work initially. I don't know why, it gave a black screen, but you could see something eh... on the video signal, which was moving.
When you moved the switch, turned it on and off, you saw very little interference.
So I insisted for a moment on turning it on and off... evidently there was a bit of oxide on the switch contact. That's gone!
That one started, it works, it works well, and therefore it can work both with the modified kernal and with the original kernal.
Of the two Commodore 1541 floppy disk drives I couldn't get even one to work. Those two, in my opinion, must have some problems.
One of the two has the engine that always runs, so it will be an electronic problem, I think.
Instead, the other pretends to read, but then returns the error, as if he couldn't read anything.
So, in my opinion - but I haven't opened it yet - it could be the belt that doesn't rotate the disk, but I'm not sure.
That should be explored a little further. In this case, however, I already have two working Commodore 1541 disk drives: the one I've had since I was little, and then another one that Matteo gave me, and they both work well.
So this one, let's say, also... eh... maybe it's also easy to fix, but it would be the third, so I'm not particularly in a hurry to get my hands on it.
Regarding IBM, then, I already had the 8530 computer with an Intel 286 processor in my collection.
But obviously, since it's a computer that I use very often, it's always handy to have another one.
It didn't work, that is, it just wouldn't start: the power supply was completely dead.
So what did I do? I disassembled the computer's original IBM power supply.
There it is closed with rivets, there are no screws, they are actually rivets that keep the power supply box closed.
So I drilled them out and replaced the entire internal board with a modern Micro ATX power supply.
However it is a very small modern power supply.
I took out the card from the modern power supply which, obviously, being smaller than the vintage one, fit inside very well.
And I fixed it with plastic supports, glued well so that they don't come off, and I, let's say, connected the respective pins of the original power supply connectors to the wires of the various voltages.
So, in modern Micro ATX power supplies the -5V is missing, because we have the +5V, the +12V, the -12V, but the -5 is missing, which instead was there in the old power supplies, the AT ones and also the IBM ones.
So what did I do? I got an LM7905: starting from -12V I got -5V.
So, if you also want to do something like this, remember that, unlike the LM7805, where the metal back part of the integrated circuit is connected to ground, in this case no, it is not connected to ground in the LM7905.
And therefore you have to interpose an insulating mica when you fix it on a metal part to dissipate heat, which in any case does not develop, because the currents involved are really, really low.
So, after modifying the power supply, it works. The computer worked quite well.
There was the problem of the classic real-time clock, the Dallas DS1287.
I didn't put the Necroware nwX287, like I did in the other IBM.
In this case I had fun modifying the Dallas DS1287, taking out the battery contacts, then milling it where it is suggested to do so and taking out two battery contacts.
There I wrote an article on my blog on how exactly to do this operation, therefore where to mill, which contact to interrupt and how to then energize the internal circuitry of the DS1287 so that it can work again.
There was also the floppy disk drive that didn't work, but I had another IBM PS/2 that arrived half destroyed, the floppy disk worked.
So I took the player out of that computer that wasn't working and put it inside this one.
So now I have another IBM PS/2 Model 30 with Intel 286 processor and Intel 287 math processor, which is perfect, working.
The hard disk also seems very new, it's fine, everything... well, everything is in good working order.
However, the IBM 8513 monitor, which Vittorio also gave me, I cleaned well, it works too.
It worries me a little more, because it's turned off twice. But it turned off on particular occasions, that is, connected to a computer that wasn't working and so we were there moving the connector - but why can't you see it on the monitor?, you can see it, you can't see it, etc. - but at a certain point it turned off.
So I wouldn't want, let's say, something to happen due to me.
Although it seems quite strange to me that a monitor can turn off because I disconnected the VGA connector.
And on a second occasion... no, it didn't go out. On the second occasion, some colors were no longer visible, but then I looked inside the connector and a contact was back.
Luckily, once that contact was replaced, the monitor always remained on.
I also tried it for several hours on its original computer, the IBM 530, and it continues to work.
So... ah, the datassette! However, I haven't tried the Commodore C2N datassette, because I have quite a few of those too, and therefore I didn't need an extra one.
Well, so this is the total of the report, the summary of the various gifts I had received from Vittorio, to know what worked and what didn't work.
I hope you enjoyed this video, even if it was made under somewhat lucky conditions.
Now I've arrived at work so I'll see you next time.
Take care! Bye bye, see you soon!