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C64 PSU

Posted: Sun Jan 02, 2011 9:08 am
by Dominoid
So I recently acquired a Commodore 64 in an unknown state. The guy that sold it to me had got it from a house clearance so there's no real way of knowing if it's knackered or not. The PSU that came with it is the black one (310200-04) and searching the internet seems to suggest that these are generally regarded as killers. The previous owner has cut off the plug so I'm in two minds as to what to do. the only source I can find for a replacement is about 15 quid which is a little pricey for my liking but at the same time, if I put a plug on this one I have, how much damage could it feasibly do to my new toy? Is there a way of testing if it's likely to kill it too?

If it's not a good idea to use the one I have here, do I have sensible options apart from the 15 quid replacements? I've seen people talking about making power supplies out of two universal transformers but I've not seen any "idiots guides" for these. Is it feasible I've just missed a great guide someone could point me to?

Re: C64 PSU

Posted: Sun Jan 02, 2011 11:12 am
by tekaotaku
use it but........whack it on a circuit breaker/trip plug thingy.........worst that will happen is it trips the plug, shouldnt damage the C64 if all goes well....

so, light touch paper, stand well back and let us all know what happens....if we dont hear from you, well.... :?

Re: C64 PSU

Posted: Sun Jan 02, 2011 11:17 am
by SexyWayne
There's also a fuse inside the C64 that should blow if anything goes tits up...

Re: C64 PSU

Posted: Sun Jan 02, 2011 12:53 pm
by Dominoid
Well, after all that, what an anticlimax. Put a plug on it and plugged it all in and nothing happened at all. PSU doesn't seem to heat up either so I'm assuming it's dead. So now It's either a replacement off t'interweb or make one a team style. Anybody know of a good guide for building one or am I better off just putting me hand in me pocket a bit more?

Re: C64 PSU

Posted: Sun Jan 02, 2011 12:59 pm
by FatTrucker
There's currently a working complete C64 with games for sale in Off Topic @ £20.

Re: C64 PSU

Posted: Sun Jan 02, 2011 1:33 pm
by Dominoid
Damn, beaten to it!

Re: C64 PSU

Posted: Sun Jan 02, 2011 1:49 pm
by FatTrucker
Dominoid wrote:Damn, beaten to it!
You could PM The Master and ask him nicely if he would mind you grabbing it instead as I'm pretty sure he's got doubles anyway and you do share a passing interest in beards. :wink:

Re: C64 PSU

Posted: Sun Jan 02, 2011 2:37 pm
by Fred83
Dominoid wrote:Well, after all that, what an anticlimax. Put a plug on it and plugged it all in and nothing happened at all. PSU doesn't seem to heat up either so I'm assuming it's dead.
If you have multimeter test psu with it or get a friend try it.

C64 Repair guide here.Lets hope we can revive it http://personalpages.tds.net/~rcarlsen/cbm.html

And lemon 64 topic on repair- http://www.lemon64.com/forum/viewtopic. ... 98a982e5c4

Re: C64 PSU

Posted: Tue Jan 04, 2011 5:36 am
by F-zero
tekaotaku wrote:use it but........whack it on a circuit breaker/trip plug thingy.........worst that will happen is it trips the plug, shouldnt damage the C64 if all goes well....

so, light touch paper, stand well back and let us all know what happens....if we dont hear from you, well.... :?
There's also a fuse inside the C64 that should blow if anything goes tits up...
A circuit breaker won't help with a C64 power supply, the issue comes from the fact that the power supply is:

A: So badly made that it can't quite meet the C64's power requirement and is prone to failure over time.
B: Has no protection circuitry which leads to overvoltage/undervoltage after failure (The overvoltage kills certain chips in the system)
C: Can be very difficult to diagnose, i tested a power supply that gave the correct readings on my multimeter but was failing under load due to voltage ripple (an oscilloscope is required to measure this)

The fuse in the C64 is only for the 9v AC line which powers the datasette and the Sid (i think), it's the 5v DC line which powers the other internals and it has no protection.

Btw, is it the C64 or C64c you own?
The C64c has reduced power requirements and doesn't burn the power supply out as quickly (if at all)

The first thing to check is that the power supply is broken, so as previously suggested i would start there.

Re: C64 PSU

Posted: Tue Jan 04, 2011 8:19 pm
by Dominoid
Aye, it does seem that it's the power supply (no readings at all off the plug) so I'm gonna have to bite the bullet and replace the power supply. The cost of it though,I'm tempted to keep the one I have as a spare and just buy another full unit. The cost of a tape deck and power supply is about the same as it'd be to just buy another commodore. It's the original C64 brown breadbin type that I have rather than the newer one, but weirdly I prefer the look of that one. I think it's just cos that's the one I had.

Re: C64 PSU

Posted: Wed Jan 05, 2011 5:59 am
by F-zero
Dominoid wrote:Aye, it does seem that it's the power supply (no readings at all off the plug) so I'm gonna have to bite the bullet and replace the power supply. The cost of it though,I'm tempted to keep the one I have as a spare and just buy another full unit. The cost of a tape deck and power supply is about the same as it'd be to just buy another commodore. It's the original C64 brown breadbin type that I have rather than the newer one, but weirdly I prefer the look of that one. I think it's just cos that's the one I had.
I agree that it would be better to buy an entire new system.
The C64c is not that sought after so you can probably pick one up with a power supply and datasette for around £20 +p&p
I like both systems although they each have pro's and con's, the breadbin has better video output and probably better sound (its a matter of taste which sid sound you prefer) but is more likely to fail.
The C64c runs cooler and is much more reliable.

You should also consider getting an s-video cable as the improvement in picture is worth the investment.

If you ever get really into the C64 you should consider the 1541 Ultimate, a quick search on youtube and goggle should explain what it is.

Re: C64 PSU

Posted: Wed Jan 05, 2011 9:01 am
by Dominoid
That looks a pretty nifty bit of kit. I can certainly see me getting one of those. Although, there's still a part of me that likes the idea of loading games from tape, listening to the squeaking and hoping it works this time, like I used to as a kid. Give it a few weeks though and I'll probably be sick of it and hankering after speed.

Am I right in thinking the c model has the same SID chips as the Atari ST had? I remember making a lot of "music" on that when I was a kid and it always sounded ace.

Re: C64 PSU

Posted: Wed Jan 05, 2011 9:21 am
by AceGrace
I often prefer to load games via tape because of the loading music. You seem to miss out on this when loading games from disk.

The ST did not have a sid chip.

Re: C64 PSU

Posted: Wed Jan 05, 2011 10:20 am
by F-zero
Dominoid wrote:That looks a pretty nifty bit of kit. I can certainly see me getting one of those. Although, there's still a part of me that likes the idea of loading games from tape, listening to the squeaking and hoping it works this time, like I used to as a kid. Give it a few weeks though and I'll probably be sick of it and hankering after speed.

Am I right in thinking the c model has the same SID chips as the Atari ST had? I remember making a lot of "music" on that when I was a kid and it always sounded ace.
When i got a c64 last year i was converting the .d64 and .tap files to wav and recording it to tape but the novelty soon wore of.
Theres just to many games to try for that method to be valid, i also like the idea of playing sid tunes on the native hardware and trying out stuff from the demo scene.
I haven't received my Ultimate yet but it has been ordered, i can't wait :)

Re: C64 PSU

Posted: Wed Jan 05, 2011 1:54 pm
by Fred83
Another method is to use an incar cd tape adapter.Connect to mp3 then load games from that.