Hi,
I am having a problem with my psu. I made it a couple of weeks ago and the output voltages were fine (around 5 and 14). I then connected the bankstick bits to the core and now for some reason the output voltages of the psu are different (about 1v and 9v). Is there something wrong with my psu board or is the c64 psu broken?
Does anybody have any ideas?
Thank you
Chris
You have to learn how to troubleshoot!
Disconnect the bankstick bits, retest voltages.
Disconnect C64 PSU, test voltages coming out of it.
If everything tests OK in isolation, then pull out the bankstick chip(s), look for short circuits in your bankstick bits, etc.
It seems that it’s the c64 psu which is broken.
Does anybody know where i can get another?
Thnak you
Chris
mouser
digikey
jameco
futurlec
They should all have switches. Any power switch should be good… Depends on what the switch is switching. If It’s wall power before any transformers, get a nice rugged one. It shouldn’t cost more than $5… I have a nice little one that lights up right next to me 
Perhaps the fuses are blown ???
Perhaps the fuses are blown ???
Quite possibly, but there is no way of getting inside unless i break it.
If the fuse is blown, there’d be no power at all.
If there’s still some voltage on the output, perhaps the transformer is half fused or something, resulting in less output. You’ll probably need a new C64 PSU. Before you plug it in, though, you should work out if your “bankstick bits” is what caused your previous one to fail. Use your multimeter to check short circuits between +5V and ground.
if it is a c64 psu, and thats what i read from your first post, you will get some power from the psu even though one fuse is blown. ([edit]: oh, wilba said that just above) On the backside of the psu there are 2 black circles. Open them and check the fuses.
I had that problem last week. check out my earlier posts.
/carsten
Fuses… Protecting our precious transformers wherever they go! (I’ve lost 2 or 3 transformers that way! (too much current))
I don’t seem to be getting any current from i at all. I guess i’ll just buy another.
Thanks for your help
Sloooowww dowwwwn Chris. Read Wilba’s posts again
Not strictly an answer to Chris’ problem. more of a question really:
If I wanted to have an internal PSU for my MBSid (afterall, who wants another cable brick to fall over, especially one as chunky as the C64 transformer), would it be feasible to take the C64 one out of its enclosure and stick it in the box with the Core/Sid boards, or would it be better to build an alternative from scratch? I guess you could build something a lot smaller with modern components, but I may be wrong.
Any thoughts anyone?
Alex
Have you read my thread?:
http://www.midibox.org/forum/index.php?topic=7631.0
As i said, i had kinda the same problem.
And have you opened up to check for the fuses on the backside of the c64 psu, next to the power button (atleast on the cpu i have, look at the picture, i have the one on the left).
/carsten
(and to Toneburst bursting in (ho ho), i have seen a thread somewhere on the forum where a guy had 2 different psu build in to his machine. New and quite small units. i just cannot find it again)
I have the the one in the middle but the bottom of it has been ripped off. I cannot see any fuses.
I think i know why it’s possibly broken. I got a bit confused with the wiring of the psu board and the connections of the core and sid.
When i turned it on there was a sizzling sound.
I then found out that i’d soldered it wrong and changed the wiring.
Would this have broken it? Is it possible that anything on the boards will be broken?
Chris
I have the the one in the middle but the bottom of it has been ripped off. I cannot see any fuses.
If yours is anything like mine, You’ll find the fuse in the mains plug.
If yours is anything like mine, You’ll find the fuse in the mains plug.
Nothing, as in 0 volts?
Do you get 240V before the transformer? what about the 2ndary side of the tranny?
Thats the C128 and amiga PSU, right?
Isnt the wiring different on this one. Check out this link:
http://www.vintage-computer.com/vcforum/showthread.php?t=896
/carsten
Nothing, as in 0 volts?
Do you get 240V before the transformer? what about the 2ndary side of the tranny?
Yeah 0v. It’s showing 240v befor the transformer but 0v after.
There you have it, fried transformer. Must be really fried to give off 0V! 
