Old c64 psu

MIDIbox SID
1

heyyy

my first post on the SID forum, never had anything to say before..

i have a very old c64 psu it s not the totally squared one, this has a “cut out” corner.

I checked the voltages and i have 5.4DC and 10AC

-Is this ok?

-Is it very advised to rebuild the circuitry especially considering that mine has to be of the 80s

-Do you guys know any special trick to open the psu? I can t see any screws but it doesn t look glued or hot glued.It seems to me that it will be enought to pull the back panel out.

The connector is a DIN (or alike) 7 pins that fit nicely to the one i got from Wilba (txx Wilba!!), counting the pins from left to right and facing the connector (so not counting in the standard way) i have 10AC on pins 1 and 7; and 5DC on pins 4 and 5

Here

http://www.c64-wiki.de/index.php/Netzbuchse

it s different

-???

txx

simone

2

10vac is normal, since you are testing without any load, but the 5vdc is regulated, so 5.4 is too high and probably indicates the supply is near failure.  There seems to be some confusion about the pinout on these.  the one you linked is viewing the jack (which seems to be the more common reference) but Wilba and I think TK have supplies with 5v on the opposite lower pin (pin 4).  Neither of my two c64 supplies even has a pin where pin 4 would be…

I share your concern about the old commodore psu, and hope to replace mine at some point.

I’m interested to see the pics you will be sharing with us of your opened psu *whack*

3

hey ya

ok so far..  i ve opened th e box and immediately trashed th electronics, diodes were almost there to burn the pcb.

(the big elec capacitor says ¨made in germany¨ eh the good old stuff :wink:

now i have left 2X 9 volts AC outputs from the tranformer

for best signal to noise ratio the 5 volts should be processed inside the psu and not in the 6582 am i right?

in this case all i have to do is to rebuild the 5 volts rectifier inside the psu and feed the 5DC and 9AC to the 6582

if anybody can confirm this it ll be lovely

simone

4

hey ya

ok so far..  i ve opened th e box and immediately trashed th electronics, diodes were almost there to burn the pcb.

(the big elec capacitor says ¨made in germany¨ eh the good old stuff :wink:

so where’s the pics?

now i have left 2X 9 volts AC outputs from the tranformer

for best signal to noise ratio the 5 volts should be processed inside the psu and not in the 6582 am i right?

the 5v reg circuit is best outside the case because of heat (not noise)

in this case all i have to do is to rebuild the 5 volts rectifier inside the psu and feed the 5DC and 9AC to the 6582

if anybody can confirm this it ll be lovely

simone

correcto

you might want to check the pinout, mb-6582 wants 5v on pin 4…  i would connect 5v to pins 4 and 5

5

..lovely,

  hey J. my camera s broken, sorry no pics atm.Also my mother is complaining about the lack of recent picture of my shorty… ah la mamma! … :wink:

simone

6

…there you go

7

weird, looks like you got the alien psu, complete with digestive enzymes…

8

hehe take a look at mine.

notice how I miserably failed to liberate the blowed fuse >:(

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185921043932738abc300f2cojpgb4f68a6b8b21bb1cae212d9ee57364cc800×600 128 KB

9

i guess i’m going to have to open up my malfunctioning spare and see how nigh invulnerable it is.

has anybody here dug into the epoxy yet?

10

hi

well i did it !

i think this is not epoxy, i am a windsurfer and i recognize the smell of epoxy from miles away and i do know how much it itches when you work with it!

The 7805 was attached to the heatsink by  a screw or rivet, i won t be able to replace that so i will just put the new7805 in place and fill the gap with epoxy dot

simone