[AUTOMATIC CAPTIONS BY YOUTUBE] on the menu today let's try to devise a new fix for a Commodore 64 color
issue even though I'm colorblind we'd better get cooking
Ad: "Are you keeping up with the Commodore? Cause the Commodore is keeping up with you!"
they seem friendly don't they oh hello chip dippers welcome to retro
recipes I've certainly been keeping up with Commodore Commodore fixes for about
35 years now and this video will be of interest to you whether you're just
intrigued by the idiosyncrasies of Commodore electronics or if you've
performed a permanent Commodore 64 pal ntsc conversion and ended up with a
black-and-white picture as some people have reached out to me for help with and
if you're wondering why you'd even want to convert between pal and ntsc actually
we went into this in depth in the video about my new Vic 2 squared pal ntsc
switcher a board that lets you flick between those modes on the fly for the
best of both worlds and that whole project was made with the support of PCB
Way because as we all know PCB way stands for Perifractic's Commodores
are black and white are yours doesn't it feel free to take a look at that video
after this one but in short pal has better color accuracy higher resolution
and more software but also NTSC machines run faster the music sounds different
and might be more familiar and pleasing to you nostaglically speaking so when
asking which is best sometimes the answer can be both but here's the rub
doing so can send you back to the 50s color wise yes so what's going on here
why is this happening well I've researched this with
one stage and the fantastic VIC2 squared beta tester Stephane and what
we think we've discovered is this old CRT screens are a little bit finicky
when it comes to getting a color sync and as part of any pal ntsc conversion
we basically replaced three things there's the Vic chip this jumper and
this crystal the power crystals frequency is roughly speaking seventeen
point seven three four four seven five megahertz roughly speaking
whereas NTSC is fourteen point three one eight one eight megahertz now in the
factory when Ladyfractic and this lady were assembling the Commodore 64 that
tests the output and make sure it provided good color sync to the power TV
if the image came out black and white there's a component critical to the
tuning of the fundamental frequency which could be adjusted and that's
important because that master lock generates the all-important color
subcarrier frequency that's the thing that the monitors failing to lock onto
for all the revision boards this was the job of the r-27 variable resistor which
looks a bit like a trim pot for new aboard revisions this was actually
achieved via a variable capacitor labeled C t1 and adjusting these could
compensate for natural variances in the crystal yeah believe it or not
everything from Vic to socket quality to Vic tip revision numbers can affect was
known as the parasitic capacitance and therefore the frequency pardoning so
when we take a pal seventeen point four seven megahertz crystal out and pop in a
fourteen point three megahertz NTSC one we're essentially taking this nice
lady's job with the factory and kind of starting over before shipping it to the
customer which is also you but if we find our newly NTSC machine fails to
then give color to are finicky monitor we can pretend we're in the factory and
adjust the same trim pot thingy sometimes that will actually fix
everything but in my case after installing them literally in my case
after installing the Vic 2 squared on this older revision machine my
good old Commodore 1084 s monitor made by Philips simply can't lock on to the
color what a fusspot I thought it was trim pot anyway let
use an oscilloscope to analyze what we call that fundamental frequency you can
see the frequency here Hey what wait a minute baby that's not what I had in
mind love to what leave okay now let's look at the oscilloscope
and we can see there's slightly below the fourteen point three one eight one
eight megahertz that the monitor expects and demands but in this case even
cranking the r27 variable resistor trim board up all the way doesn't get the
fusspot working you know the resulting frequency is still too low and really
that's because we're expecting a trim pot that worked for Commodores
thirty-five-year-old crystals to work on modern smaller ones from different
manufacturers that are likely to have different tuning characteristics and
Commodore just didn't really anticipate us doing that the damn fools so somehow
we need to tune the frequency up a bit further than the dial allows and our
theory is that this little 16 Pico farad capacitor labeled C 70 can help you can
see how it's laying right between the Vic chip the trim pod and the crystal
area basically adding capacitance with a capacitor lowers frequency so if sixteen
Pico farad is lowering too much well why don't we try about half of that if we
put a seven Pico farad cap in its place it should lower it less this should
raise the frequency just enough for the monitor to get a sync
but there's one more rub not a big one but my PCB is screwed in which is
usually fine but also these mini grabbers is fiddly to get off and on
then there's this extension cable and the PAL NTSC switch is bolted to the
case from right over the PCB screw that we need to
screw yeah so I'm going to show you how to replace capacitors like this from the
top without having to remove the PCB quick disclaimer this isn't really the
right way to do it why am I American and as it's only one
quick mod and Puppyfractic needs feeding I'm gonna do this the speedy way this is
my Commodore 64 but of course it's up to you how you mod yours when I next get
the whole board out I can always tidy things up underneath end of disclaimer
I'm American again all right enough talk let's get cooking
so there it is how to fix Commodore 64 color using a 13 pence capacitor
makes cents and if you order a VIC 2 squared and you'll find
that seven picofarad capacitor included in your kit just in case your TV's the
trim pot fuss pot too by the way don't worry they love each other really
now I mentioned I'm color blind actually that's kind of a misleading term it
isn't really a blindness more the people with protanopia see less red and green
than full sighted people so the color deficient is a better term thank you
very much third imagine you load an image in
Photoshop then reduced the red and green by about $0.50 that 50% if you're not
colorblind this is how things would probably look if you were just as it
does to the 8% of men who are you know for some reason it affects far far less
women than men and they say men have it easy and if you do have protanopia like
me well hello firstly but here's how a photo
probably looks to a color sighted person that's that's just weird I prefer it our
way by the way those colorblindness glasses I've tried them they don't
really do much in my opinion apart from help people make viral videos
with color spelled strangely like' and subscribe' everybody there seriously
that may be red-green color deficiency is why I love Commodore basics so much
the purple screen of life you know that's blue right the blue screen of life
well now that this c64 has been rescued by Perifractic there's only one thing
for it let's play rescue on Perry fractalus
now this motherships bound toward booster Ranger practice down there's
where it gets sticky the Jackie's have packed the planet with
a remote-control weaponry and suicide saucer there may even be troops it's all
we know now suit up you're the only ones who can pull this off some of those
pilots have been down there a long time thumbs up fly guys going out get us a
future
rescue on fractal as' a dangerous mission behind Jack Eli's you joined the
elite rescue squadron and pilot your valkyrie fighter through the craggy
landscape of practice explore every peak and Valley every Canyon searching for
stranded space pilots testing your skill against the dreaded jaggies who have
invaded our sector of the galaxy land your fighter on practice just long
enough to rescue those either core pilots from the planets treacherous and
hostile atmosphere pilots in ranged he's on the approach and commander he looks
beat oh he's pounding on the rear airlocks well I'm open kid okay you am I
glad to see you I knew you guys could bail us out
my co-pilot has right I'm low on fuel what are we gonna do we have to go to
the mothership who's dis firing here we go
we're gonna make it to the mothership
all right and again like I do that come on buddy
thank you for your help
what are you saying
I wonder what they're saying in English
"Ahhh"