Which C64 power supply has the most juice / current ?

[Futureman]

As I got my kings randsom of SID chips in my hands, I stuffed all 8 and my MB-6582 wouldn't start up.. I remembered something about a fully stuffed 6582 not always powering up with some C64 power supplies so I thought I'd ask.

I kept on removing Sids, untill I got to 4... then it worked...

Mine is the beige solid brick one.. I have yet to try the black one with ventilation holes.. are there any more types?

Regards

Mike

[Goblinz]

I know of four types. There's the beige brick with the ridges, the black one, and two types that are wedged, one with a longer wedged face than the others. There also seems to be differences with in the models. IE some ony have the needed pins and some have a couple of the Pins reversed.

[Wilba]

Yep, that sounds like a weak C64 power supply, unable to deliver enough current on the 5V supply (i.e. less than the label says it can).

Yell out if you need a good black one with ventilation holes.

[strophlex]

Any idea which ones are powerful and which are likely to fail?

[Futureman]

Weird... I powered it up today with 4 sids and it was fine, so I added another and another and another and another... voila.. it's running off 8 ?

It must be on the threshold of working / not working ? That is a bit perplexing.. hmmmm..

Regards

Mike

[Wilba]

It could be temperature related... on a hot day, 8 SIDs overheat the voltage regulator (or transistor) inside the brick, but on a cold day it doesn't. Or maybe it works with 8 SIDs on a cold start, but not if you were already running warm for a while with less SIDs.

[Futureman]

Any idea which ones are powerful and which are likely to fail?

Looks like Wilba said the black ones have more juice..

It's all redundant for me now, I've got mine running off a switchmode power supply.. Apparently it can deliver up to 6A !!! for the 5volt rail..

I guess I'm cross posting now, but I was surprised about the lack of induced noise into the Synth when running off a switchmode PS considering all the no-no's I've read about them and audio circuits.

Regards

Mike

[strophlex]

Any idea how much current will be drawn from the 9V? I think there was a 2A fuse in my supply.

[Futureman]

Any idea how much current will be drawn from the 9V? I think there was a 2A fuse in my supply.

To quote Wilba-

"Based on datasheet calculations, the 5V supply usage is ~1000mA.

PICs are 23mA each, 6582A SIDs 70/100mA each, LEDs 100mA max, LCD ~280mA.

If the SIDs are at the max current, then it's ~1200mA.

9V supply usage is ~320mA."

Regards

Mike

[Goblinz]

Could be that the power supply is on the way out ????

Mine started doing weird things before the 5V line cut out last week.

[m00dawg]

It's all redundant for me now, I've got mine running off a switchmode power supply.. Apparently it can deliver up to 6A !!! for the 5volt rail..

I guess I'm cross posting now, but I was surprised about the lack of induced noise into the Synth when running off a switchmode PS considering all the no-no's I've read about them and audio circuits.

Uhh..., are you feeding the 5V regulator with 5V? I assume you removed your regulators if your PSU is supplying 5VDC? I'm in the "don't use a switched power supply" camp (I'm in the "I'm building my own damn PSU" camp :) ), but I was forced into using one when I was trying to figure out how to power my first CORE + SID. I just grabbed one that was rated above what I needed to feed my regulators (I think I used 12VDC) and it worked ok. I still wouldn't advise that but *shrug* if it works for you :)

[toneburst]

Anyone know if it's possible to make a smaller, less brick-like external PSU for the MB-6582 with more modern components than the original Commodore64 ones?

a|x

[m00dawg]

It's not smaller (yet, anyway), but easier to work with. Or at least that's the plan:

http://www.midibox.org/forum/index.php/topic,12695.60.html