LIVING WITH YOUR COMMODORE
POWER SUPPLIES

AUTHOR: BILL DEWITT
        B & B COMPUTER REPAIR

FROM: MEMPHIS  COMMODORE
      USERS CLUB

     Your Commodore 64 may have one of three power supplies. The first version was a repairable non-sealed unit. The next two versions are sealed in epoxy and are not repairable. If you are unsure of which one you have, flip it over and look at the bottom. If it has four screws and a rectangular vent it is a repairable unit. If the power supply has no vents or assembly screws it is a sealed unit and is not repairable (throw-away version).
     
Don't be scared if it is sealed, some power supplies last like a Mack
truck and never give any problems. Other people have not been so lucky. The
C-64 power supply is one of the weak areas in the computer. The amperage
developed is barely enough to meet the needs of the computer. Adding on any
items that use power from the computer just strains the power supply more. If
you want an idea how hard your power supply is working just put your hand on
top of it after a couple of hours of computing. Hot enough to keep coffee
about right? You bet. Most C-64 owners are aware of the problem and I sure
don't need to remind them. Your saying to yourself right now "So I have a
problem, how about some answers!"
    
Since this heating up problem causes the supply to become unstable and
break down, this is were we can make a difference. 
     
If you are a short duration user you can get by as is and probably won't
cook your power supply. If you average a couple of hours at a time you need to do something to help cool the unit off.Try placing the power supply on an
aluminum pie pan. Turn the pie pan upside down and put the supply on it. This
will radiate off some of the heat and keep the floor from insulating the
bottom of the supply. Another way is to mount the supply on metal "L" brackets on the side of your computer desk. This allows maximum air flow around the power supply and will help it stay cooler.
     
OK, so you are a heavy user and perhaps your computer stays on days at a
time. You need to invest in a cooling fan. I have found that Norelco makes a
room air freshener that fits the bill.
     
It is a small white unit with a flat, vented top that is just perfect to
set a supply on top of it. I found them at Super D drug store for $6.00. A lot better than $39.00 for a new power supply, huh. They also freshen the room. The power supply will probably cool better on top of the air freshener if you turn it upside down. This will give the maximum effect because of the shape of the power supply sides.
    
Well how do I know if my power supply is failing? I thought you'd ask
that. There is a few ways that don't require any special training or test
equipment.
     
Computer is completely dead. No power light or anything. In this case
borrow one from a friend and see if the computer comes up and performs
normally. That one is easy. Another way is if the little red power light on
top of the keyboard starts to dim and then brightens and later dims etc. When
this occurs the computer will often act like it has a mind of it's own. It
will shift to graphics mode or maybe jump to the opening screen. It can even
cause alot of load errors. If you have these symptoms try putting the power
supply in the freezer. That's right freezer. After it gets cold run it again.
If it acts normal for a while and then begins to act crazy again it is a
cooked power supply. Get a new one.
     
You can buy power supplies from nearly every one listed in any computer
magazine. Are they good? Try them and let me know. One after market supply
that I have tried is one built by RECOTON. It's not any better than
the factory original but it does have a one year warranty. Ken has tried
several on the CUP and doesn't appear to like any of them. A BBS will put the
true test on a power supply. Some of the original Commodore units are
available through the Club. If you need one the education Director (Adolph)
knows how to get hold of them.
     
I hope this helps you have a longer lived power supply and more fun with
your Commodore. Commodore is still one of the most successful and powerful
computers you can buy for the money. Don't you just love-em?