Dead Plus... What to do?

[iMac600]

I have a dead Macintosh Plus (early non-Platinum) just sitting here. I think for the most part a lot of it works, despite the PSU being a little bit flaky due to bad joints and the CRT rings are slightly out of whack. The big problem is that this machine has no ROM chips. I took the ROM chips from this machine, which was in pretty bad shape, and dropped them into the 512Ke to get it working again. The main issue is that now leaves me with one dead Mac Plus.

I'm not sure what to do with it. I could very easily throw it away, but at the same time I feel as though i'm wasting a potentially good Compact Mac. I've also been trying to source ROM chips to get it working again, to no avail. Eventually it's only going to get in the way.

So MLA, what should I do with it?

 

[macgeek417]

er... get a ROM flasher and some ROM chips, and make ROMs?

 

[macgeek417]

(or see if anyone on here has a rom flasher and is willing to make some for you)

 

[Mac128]

So MLA, what should I do with it?

Well, it's certainly a good candidate for a mod. Considering how many Mac Pluses there are out there, I would suggest that it won't be missed. Throwing it away is a waste though. List it on eBay and at least attempt to get it to someone for the cost of shipping. You'll likely find a taker with more room to spare.

In therms of resuscitating it, you can probably find a complete logicboard on eBay faster and for less money than a pair of 128K ROMs. However, it sounds like the PSU is in bad shape, so how dedicated are you to the tedious repair work it may require if this is not to be a major machine for you?

If a computer mod doesn't work for you, then you can always make it a practical household item ...

 

[iMac600]

Well, it's certainly a good candidate for a mod. Considering how many Mac Pluses there are out there, I would suggest that it won't be missed. Throwing it away is a waste though. List it on eBay and at least attempt to get it to someone for the cost of shipping. You'll likely find a taker with more room to spare.

I've considered that, for sure. I don't think there's any demand for broken Compacts here in Australia though, especially if they have multiple problems.

In therms of resuscitating it, you can probably find a complete logicboard on eBay faster and for less money than a pair of 128K ROMs. However, it sounds like the PSU is in bad shape, so how dedicated are you to the tedious repair work it may require if this is not to be a major machine for you?

The PSU has heavy corrosion (from a leaky battery) around the switch contacts, which i'd imagine can be sanded off. It seems like some of the solder joints are broken as well. I can't pinpoint just which ones are broken, but I can go around and do all of them if I have to. Not a difficult job. That said it's not set to become a major machine at all, the 512Ke already has that role filled.

I was curious if anyone had electrically modified the power and CRT circuitry to take signals from another source. Like... if I were to install a TV tuner in the base, could I rig the video circuitry to the signal outputs on the tuner? Of course I don't just mean a TV tuner... could anything at all be connected up? Just a curiosity.

If a computer mod doesn't work for you, then you can always make it a practical household item ...

Well it's already making a pretty convincing doorstop at the moment.

 

[Osgeld]

(or see if anyone on here has a rom flasher and is willing to make some for you)

I have a rom burner, but no blank proms or originals

 

[Bunsen]

I was curious if anyone had electrically modified the power and CRT circuitry to take signals from another source. Like... if I were to install a TV tuner in the base, could I rig the video circuitry to the signal outputs on the tuner? Of course I don't just mean a TV tuner... could anything at all be connected up? Just a curiosity.

Somewhat related:

Power R Video Adapter

Why the unusual frequency?

Core2Duo Color Classic

http://www.applefritter.com/node/9437

Poor Man's Greyscale 640x480 SE/30

You may (or may not) find relevant information and/or inspiration in the MPxPlayer and EvilTim's other projects.

It really is possible to interface a PC to any kind of fixed frequency CRT monitor, it's just a matter of getting the video timings right.
VGA compatible PC graphics cards are extremely flexible when it comes to generating unusual video resolutions. It's the software which is the tricky part. I think it would be much easier to do this sort of thing with Linux (Xorg) than MS-DOS...

I don't recall whether it was that hack, or one of his other CRT hacks, but IIRC he also converted a monochrome CRT to greyscale by feeding the intensity level into where the brightness knob used to be.

Myself, I wonder if doing that, and some analogue board hacking a la the Color Classic a/b hacks, would be an even simpler way of getting VGA (or greater) greyscale, than Stuart Bell's Poor Man's Greyscale.

 

[Bunsen]

Monitor repair FAQ - has lots of info

 

[iMac600]

Go figure. I'd have more success eating cashews through a straw than attempting that, especially considering I have very few resources to throw at it.

I'll have to think about this. I'm not sure there's much I can do for it. I'd still like to get the logic board working again if possible, but without a current source for the ROM chips it's an outside chance. I'll keep looking though.

 

[Bunsen]

EvilTim's other projects.

IIRC he also converted a monochrome CRT to greyscale by feeding the intensity level into where the brightness knob used to be.

My bad. It was a colour CGA monitor (digital input converted to analogue)

Modifications to the monitor boardRemove the red, blue and green gain pots, the video signal goes in where the wiper (middle leg) went).

Note that he built a buncha other stuff to make it work, too.

Still...

 

[Bunsen]

Another relevant thread:

Converting the video signal from a Mac Classic logic board?

My thoughts:

VGA on compact CRT?

TV may be somewhat easier - or just as hard.