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View Full Version : c64 rescued from attic and doesn't work - help!



ethanthej
March 25th, 2007, 03:43 PM
I rescued my old C64 from my parents' attic today, took it home, hooked it up, and it doesn't work.

Bleah.

Here's what's wrong.

I have hooked up the monitor to the hard drive/keyboard, and everything is connected correctly. When I turn on the computer, I get a bunch of noise and garbled images on the screen. It looks like it's trying to load the startup screen, but every time I turn it off and turn it back on again, I get something different. Most of the time it looks like the V-hold is way off, but that's not it, because it's cycling really quickly and I have a garbled screen, if anything. Sometimes, however, I get a solid color screen - orange, purple, green, etc. I never get to the loading screen.

My partner thinks there's something wrong with the video card. Is he right, how do I get a replacement, am I screwed, etc. I hope I'm not looking at a dead c64 because I've also rescued a huge box of games that I want to check out. :-)

Thanks!

Druid6900
March 25th, 2007, 05:20 PM
I'll assume you mean floppy drive, not hard drive, and there are any number of things that could cause that problem (which may be why it was in the attic in the first place) none are which can't be repaired.

Terry Yager
March 25th, 2007, 05:59 PM
Some people refer to the main unit as the 'hard drive'. (I've even seen this in college textbooks). I've always taught people to refer to 'The box part, the typewriter part, and the TV part' when trying to explain thier PC troubles to me. Oh yeah, then there's the 'foot pedal'...

--T

Druid6900
March 25th, 2007, 07:45 PM
I just have them write it all out in their favourite colour crayon :)

carlsson
March 25th, 2007, 11:12 PM
Is that an old, dark grey C64 commonly known as "breadbox", or is it the newer, light grey one (C64C) that is more flat but slightly deeper?

You may look here, in particular the two articles "C64: chips vs symptoms" respectively "C64C: chips vs symptoms" depending on which model it is.

http://personalpages.tds.net/~rcarlsen/cbm.html

One thing for certain. No C64 should boot up with orange, purple, green unless you have some fancy cartridge plugged in. The standard boot up screen is dark blue with a light blue border and ditto text. Perhaps the light blue can be mistaken for purple, but green for blue takes a lot of imagination.

The C64 doesn't have a "video card" like IBM and subsequent computers. It has a video chip (think of it as integrated graphics if you like) called VIC-II. From the list of symptoms in the links above, it should not be the cause of your problem, but rather some other chip. Depending on who assembled your computer (roughly put), chips may be in sockets or soldered directly to the board. If they're in sockets, you have a fair chance to replace any broken chips, but it also means you need to get in touch with someplace who have matching chips, and that you're certain which one(s) need to be replaced.

Commodore 64 should still be pretty cheap on eBay, so if you find this one beyond repair but want to relive your childhood (?), it should be well affordable to get one claimed fully OK.

verlwb
April 26th, 2007, 09:39 AM
Is that an old, dark grey C64 commonly known as "breadbox", or is it the newer, light grey one (C64C) that is more flat but slightly deeper?

You may look here, in particular the two articles "C64: chips vs symptoms" respectively "C64C: chips vs symptoms" depending on which model it is.

http://personalpages.tds.net/~rcarlsen/cbm.html

One thing for certain. No C64 should boot up with orange, purple, green unless you have some fancy cartridge plugged in. The standard boot up screen is dark blue with a light blue border and ditto text. Perhaps the light blue can be mistaken for purple, but green for blue takes a lot of imagination.

The C64 doesn't have a "video card" like IBM and subsequent computers. It has a video chip (think of it as integrated graphics if you like) called VIC-II. From the list of symptoms in the links above, it should not be the cause of your problem, but rather some other chip. Depending on who assembled your computer (roughly put), chips may be in sockets or soldered directly to the board. If they're in sockets, you have a fair chance to replace any broken chips, but it also means you need to get in touch with someplace who have matching chips, and that you're certain which one(s) need to be replaced.

Commodore 64 should still be pretty cheap on eBay, so if you find this one beyond repair but want to relive your childhood (?), it should be well affordable to get one claimed fully OK.

This is a me too add-on:

C64 with "black screen Disease". Thanks for the above links.

Mine is circa 1983 "breadbox" - only socket is the SID.

Any one do repairs???

Druid6900
April 26th, 2007, 07:43 PM
As a matter of fact, yes, someone does.

wop
April 29th, 2007, 03:07 PM
I remember my original power supply used to overheat... in fact most of my friends always had power supply troubles too. They weren't serviceable units because the whole circuit board/transformer and all was entirely encased in some sort of epoxy material.

What I do remember is when my power supply would start to fail, the red power LED would dim and all kinds of weird things would happen to the screen, including what looked like a serious vertical hold problem.

The first thing I would try is a different power supply (ebay). If you can somehow determine that the logic is working (type in a command to access the floppy drive or something and see if the drive reacts) then have a peek at the RF Modulation section on the main board. It's where the video connector plugs in and is probably shielded by a silver looking "box". Look for cold solder joints.. anything easy...

verlwb
May 2nd, 2007, 05:57 AM
I remember my original power supply used to overheat... in fact most of my friends always had power supply troubles too. They weren't serviceable units because the whole circuit board/transformer and all was entirely encased in some sort of epoxy material.

What I do remember is when my power supply would start to fail, the red power LED would dim and all kinds of weird things would happen to the screen, including what looked like a serious vertical hold problem.

The first thing I would try is a different power supply (ebay). If you can somehow determine that the logic is working (type in a command to access the floppy drive or something and see if the drive reacts) then have a peek at the RF Modulation section on the main board. It's where the video connector plugs in and is probably shielded by a silver looking "box". Look for cold solder joints.. anything easy...

Thanks for the info: will check the voltages and watch the LED. I guess I did not say that what i get is the black screen. When it was first pugged in I had that out of memory error for a split-second then the screen went to the black and you know there is a video signal but as some have discribed it as really bad vert. sycn problem. Turning it on and off quickley gets you a flash of a blue and red line as it scrolls verticly.

verlwb
May 2nd, 2007, 06:01 AM
As a matter of fact, yes, someone does.

And....... does "someone" live any where near Nebraska?

:confused: