Hi everyone and welcome back to the Sawickipedia! This is our first video in our
look at the many consoles that you see behind me.
We're gonna be going through all of these one by one,
digging into repairs, mods, restoration, all that kind of thing. So first up we're
gonna look at the classic Commodore 64 which is these two guys right here. Still
one of my favorite 8-bit computers from back in the day, we used to have one of
these at the home, the very first computer that I ever actually had. So if
you've got one of these lying around maybe in the attic or you're looking at
purchasing one online there are a couple of things you should do before you
actually go plugging it in. As you may have heard these have a pretty
bog-standard power supply, now back in the day this wasn't such a big deal but
as these things age the components tend to deteriorate and they can get so bad
that they'll actually destroy your commodore 64. So let's talk about the
power supply, there are three different ones so that's sort of year latest one
which is probably the most common, you've also got one that's a bit more classic,
and finally I think this is the original black one. Now all of these will
put out nine volts AC and five volts DC power. Now the AC line is generally
pretty solid and usually you won't get any issues, if you do you'll usually
notice on either the SID chip which is the sound chip or the VIC-II chip which
is the video chip, so you'll get some distortion or issues there. Now the five
volt DC line on the other hand can cause many issues, it actually powers most of
the sensitive chips like the CPU, ROM, RAM, that kind of thing and the five volts
can go very bad very quick, and if this happens you're gonna end up with
some fried chips, and not the tasty kind. Now given that these chips are pretty
precious and they're not something you can just grab new off the shelf, or form your
local takeaway we definitely what don't want to destroy them. So before we brush
up on our BASIC skills or fire up Bubble Bobble we need to see what kind of
condition our power supply is in. Okay so in order
the test our power supply we'll just need a basic multimeter, the other thing
you'll need is either some tweezer probes like this one, otherwise if you've
got just a little clamp to hold the socket while you probe it.
You don't want to slip while you're getting a good probing, so set your
multimeter to AC we'll switch the power supply on and assuming that it doesn't
instantly let out the magic smoke we'll get to probing. So first up on the AC
line we're looking at pins and 6 & 7 which are the two pins at the top of the
connector, so if you see there's a little divot up the top, the two pins closest to
that are six and seven and it looks like we're reading about 10 volts AC which is
spot-on where we want to be. Anything sort of under 10 volts or over 11 volts
on the AC line is potentially dangerous so it's probably not advised to
use the original power supply if you're getting anything outside 10 or 11 volts.
So that looks okay so we'll set the multimeter to DC volts and this time we're
going to probe pins 2 and 4 or 2 & 5, so again looking at the plug the pin
opposite the little divot, so right down the bottom is pin 2, and then the ones
either side are 4 & 5. So some of these plugs will have only pin 5, some of them
pin four won't have any voltage on it but pin five will, but either way pin two
which is the one in the middle is your ground, and we'll try pin five and see if
we get any results from that. I'm not seeing anything from pin five so we'll
try two and four and see if we get anything from those. There we go
so 5.19 volts DC which is probably right on the limit of where you
want to be on the five volt line. Anything over 5.2 I wouldn't
recommend using the power supply, and yeah likewise anything sort of under
4.9 it's probably a dodgy power supply as well. So this is somewhat safe
but as with all these it's recommend going for an aftermarket solution for
your Commodore 64 as these will all eventually fail. Some of these I think
these two it may be possible to replace the the 5 volt regulated line so we
might look at doing that in a future video,
but this one on the end here there's pretty much no chance being that
the actual entire power supply is encased and resin or potted as they
call it. So maybe I would do something with these two but if this one's not
working it's going straight in the bin, there's no point in even messing around
with it. So let's just plug in this next one, as you can see on this one it's
actually got a lot of the unused pins removed, you'll find this fairly
often especially with the newer model power supply, but even this one has the
unused pins removed so we've only got the two AC pins at the top and then pins I
think it's four and two for the DC. So go back to AC and just check these two up
the top and we're getting about 9.9 which is which is okay. Let's
just check the DC and I'm getting 5.14 which is which is also
okay, so it may be safe to use this one as well. We'll just check this one and
yeah once again you can see the unused pins are removed from this power
supply. So back to AC we'll just have a look, get all this crap out of the way,
we're getting about 10.3 on the AC which is fine. Not getting very good
contact, oh there we go, right spot on five volts on the DC so if I was going
to use either of these I would definitely go for this one at this point
it seems to be the safest option. That's a basic check there, the next test we can
do is to actually hook up a load to these power supplies and see how they
output that five volts under load. Just quickly before we go any further this is
kind of funny you can see on this power supply which is this plug here
it's actually got pins four and two, whereas on the newer one which is this
one here it's got pins five and two, so you're gonna come across this if you're
doing this sort of thing often. Okay so in order to test these power supplies
when they're under load I've got a 10 watt 3.3 ohm resistor
hooked up to these two power supplies, and obviously hooked up to our five volt
lines in the power plug. Just make sure that when you're doing this you don't
short those two pins together because then you'll definitely probably kill
your power supply pretty quickly. So yeah as long as they're separated and we've
got our load hooked up we should be getting still about five volts across
these resistors. This one is getting about 4.4, the other one it's
getting about 4.3. So in this state this is sort of
simulating the Commodore 64 at its maximum load because we're pretty
much pulling about 1.5 amps out of the five volt line which is sort
of the maximum and these things are usually rated for... they're rated between
about 1.5 and 1.7 amps. So yeah we can leave these set up for a
little while just to see if there's any difference over time, but at the moment
still getting 4.4 and 4.3. These resistors are also
going to get pretty hot so best not to touch them. Actually we can have a look at
what they're that at the moment, yeah this one's already up to about sixty odd
degrees Celsius, power supplies at about 26, and again yeah that one's
already up to 70 and power supplies at 23. So I'll keep monitoring these, I
won't leave them as they are because they will get quite hot and this is only
cardboard here so we don't want to start a fire, but I'm gonna monitor these for
the next half an hour see how they go. I might also put these resistors in series
across one of the power suppliers which will give us you know about 0.75 amps
which will sort of simulate the Commodore at an idle state rather than
at maximum load, and we'll do a couple more measurements then, but I'll leave
these hooked up for now just so we can monitor them. Okay so after about half an
hour we're still getting 4.4 and
4.3. These things are about at about a hundred degrees now, the power
supply is on the other hand have only got up to about thirty degrees Celsius,
so they're not getting too warm. So let's disconnect them and I'll hook one of
these up in series just so we can see what the draw is like
when we're not running at full load. Be careful not to actually touch these
because they'll be bloody hot. Okay so just bodgied up the resistors in
series across this power supply and it's reading about 6.6 ohms. So let's switch
back to volts DC and see what our drop is like. See now it's about 4.76
again not ideal with a good power supply you should get a constant 5
volts regardless of the load at least up to its maximum reading. Not ideal but it
should be okay to use with our c64. Like I said we'll explore replacing at
least part of these power supplies in the near future. Let's just hook up
the other one and see what that does. So you again I've hooked up the
resistors in series and now we're connected to this power supply over here
and we're getting about 4.64 so a similar sort of drop from when
we we're at a full load. This one tended to drop more voltage than the other one
and I imagine the black version which I haven't tested yet, but I'll test it out
let you know if anything funny happens there, but I imagine it's going to be
somewhere within the same range. At the moment I'm pretty happy to use
either of these power supplies I'll probably prefer to use that one because
it's a little bit more stable before we get too excited and plug this in we're
just gonna open up the commodore 64 and have a look in there just for any
oddities. As i said at the top of this video we don't want to jump straight in
and end up killing our Commodore 64 straightaway. So let's open one up and
have a look if there's anything unusual going on inside. Okay so this is our
fairly standard breadbin model, looks like one of the keys is broken but
we'll get to that in a later video. Interestingly enough there is a
little switch here that somebody's added, I'm guessing that's a reset switch but
apart from that the screws look to be still intact and I can see that the
shield is still on there. So we'll start by opening up these screws, alright let's
have a look, as always for these things just disconnect the power LED and the
keyboard cable, it can be a bit tight but just try and be gentle. It's a little bit
dusty inside but not too bad, I'll just put that aside for a minute and remove
this clip from the cartridge port. Here we go so it is quite dusty inside, okay
so I'll just quickly clean this out. If you've got a can of compressed air
that'll do, otherwise just a nice soft brush, in my case I've got a nice handy
air compressor with air gun so this will do the job quick smart.
All right nice and easy. All right so now we've got most that dust out of the way
what we're really looking for here is any signs of sort of bulging capacitors
especially, well pretty much, just the electrolytics. So there's a few along here
in the power supply section, usually a couple up at this end as well, one over
here, and there's usually a couple just around the middle of the board as well.
At the moment they all seem more or less okay, none of them are really sort of
bulging out or leaking that I can see, and yeah there's our little hook up
there which does seem to be just a reset switch. But all in all it doesn't seem too bad.
So now that we're confident with the our Commodore 64 power supply and
everything internally it looks okay power it on see how you go. If it still
doesn't power up stick around because coming up next week we'll take a look at
the diagnostic and dead test cartridge, and I've got one here that I know
definitely doesn't work so we'll delve into some repairs and then coming up in
future weeks we'll look at the video and audio output to try and sharpen both of those
up, and also try and sharpen up some of these cases, get them looking a lot
better. So yeah be sure to hit subscribe if you haven't already and we will see
you in the next video. Thanks for watching the Sawickipedia, cheers!