Okay, so I got a new C64 to replace the 128.  Works okay, but it tends to flicker and black out -- black screen, no response -- intermittently.  Also, the background hum is pretty loud.  A little research has suggested that this may be a power supply issue.  I am wondering if I can use the power supply from a (newer) Commodore 64C?

The original brick reads:
INPUT: 117V 60Hz 40W
OUTPUT: 5VCC 7.5W 9VAC 2.5VA

The new one reads:
INPUT: 117V 50/60Hz 40VA
OUTPUT: 5VDC 7.5W 9VDC 6.7VA

Will this new power supply kill my breadbox?

(Okay then.  Please excuse me for veering slightly off-topic, as I have replaced the 128 with a 64.  I'm having trouble finding a C64 forum that will let me log on.)

Anyway, I got a C64 yesterday, via Craigslist.  It will work fine for 20 minutes, then shut down.  Blank screen, no sound or response.  When I reboot, it stays on for just a few seconds then shuts down again.  Something is overheating?

I also notice that the sound is a bit soft, and that the background noise -- that light "whirring" that kind of sounds like a small electric motor or fan -- is a bit loud.

Oh, and the basic algorithm for the paddle-theremin is:
POKE 54273, 255-PEEK(54297)
Voila!

That sounds very cool.  What I did was, since there are 2 paddles connected, I used one to "sweep" the pitch on the hi-freq oscillator, anywhere from 0-255, and the other to control other effects.  Or, with just one paddle, use the fire button to turn sound on/off.  I also had a second voice harmonized with the first.  It was all in BASIC, and the program was only a few lines!  Commodore machines are THE BEST.

Then, of course, I blew the sound chip....

(...By the way -- the reason I know about programming paddles is that I had used them with the C128 to make a sort of "virtual theremin."  I used one paddle for pitch, and the other for pulse width, filter or ring modulation.  It was beyond awesome!)

I just discovered that the game "paddles" (not the joystick) do not work, and they were also used by the SID chip, right?  So I bet it must certainly be the SID that I fried.

Where can a fellow get a new SID chip?  Does anyone in this forum sell them?  Are they cheaper than just buying a new computer?

So, questions, before I crack the thing open:

Is there a way to be sure that it's the SID, and not some other issue... I'm still wondering if it isn't a bad connection, or could it be a bad fuse?

Will I be able to look at the SID and know right away, "oh, yeah -- this thing's fried."

How delicate is this operation?  I assume we're talking soldering, right?  Do I want to be doing this myself, or should I find someone with experience?

AND... living out here in Fumbuck, Wisconsin, is there a way to find like-minded geeks who would be able to help?

Thanks again!  I was REEEALLY into some fun programming when this happened... just sickening.

Oh, well OF COURSE I did it with the power ON.  Stupid stupid stupid!  So I guess that's probably what did it.

As I said, I do have a 64, which should have a SID that I could swap out, right?  Well, I have to get someone else to do it, actually... obviously, I tend to turn things like that into a disaster.  Even much much simpler things.

Anyway, this is useful information.  Thanks much!  I'll let you know how it turns out.

I have checked the cable, and wiggled it around a bit, and sometimes the buzz gets a little louder or softer, but that's it (this does make me think it's a connection issue).  Sadly, I don't have another cable at hand to try.  I have a C64 cable, but it looks like it has a different pin configuration.

I should mention that the last thing I did before this trouble started was to try to connect the RCA plugs into an adaptor so I could plug it into a mixer.  When I realized I didn't have the right adapter, I plugged it back into the monitor, and that's when the trouble began.

Regarding composing, I haven't heard of those particular competitions.  I bet those are for purely "chiptune" works -- I'm not enough of a programmer yet to get the music I have in my head to come out of the Commodore without using some editing software on my PC.  I also want to use my Moog synthesizer for it as well.  (Wouldn't a Moog/C64 duet be fun?)

Thanks!

Same thing recently happened to me.  Had a 64 my whole childhood, recently learned my parents THREW IT AWAY.  Couldn't believe it.  Anyway, looked everywhere for a new one, finally found someone who had a 128 they let me use.  How funny is it to look at and try out a 30-year-old computer and be like "Dude!  This is AWESOME!"

Well, I hope it's not the SID.  If it were, would it make a big loud buzz all the time, not just when it's supposed to be making sound?  It sounds like a 60hz ground loop hum.

I do have an "extra" c64 which doesn't work, so I should be able to use it for "spare parts."  Since I want to use this machine primarily for music, it would be awfully nice to get the sound back online.

(I'm a composer who'd like to throw his hat into the "8-bit music" ring...)

I recently acquired a C128.  It worked great for about a week, but now there is no sound other than  a loud BUZZ.  The buzz only occurs when the audio cable is plugged into the monitor, so I don't think the monitor itself is the problem.  Picture is fine, and there are no other problems I know of.  But there's no sound other than the buzz.

Any ideas?