Everyone knows the Commodore 64, even if they've never used one.
Slightly less well known but far more useful in this day and age
is the Commodore 1702 video monitor.
These little guys were introduced around 1982 as an alternative
to using a crappy TV for a monitor on your Commodore 64. And what
a difference it made! The 1702 gave you a beautiful crisp image
and handy front A/V inputs in a tiny stackable package. They even
had a pair of RCA jacks on the back for separate Chroma and Luma
input. These days we'd call that s-video, but at the time they
just called it Commodore video. Either way you got a far superior
picture than any composite monitor or TV could manage. It's no
wonder people found uses for them that Commodore had never intended,
such as in TV studios or security rooms. And even 28 years later
most of them are still going strong.
Now of course we have LCD TVs that'll outshine it in brightness
and colour while being sharper than its designers could dream
of, but the sheer versatility, ruggedness and thrift store availability
of these things means they're still seeing use. In fact, there's
one area where these little beauties can outperform a modern LCD
TV.
Scaling.
LCD, Plasma and OLED screens are all fixed resolution devices.
Their screens are made up of hundreds of thousands of tiny squares,
each of which can change colour to become part of a larger image.
For the image to look sharp and clear, it needs to be the same
resolution as the screen, meaning it has to be made up of the
same number of tiny squares. So when you give it an image which
is too big or too small (Say watching an old VHS tape on a modern
1080p TV, or trying to watch a 1080p blu-ray on a 720p TV,) the
image has to be stretched or squished to fit within that fixed
grid of squares. The results are seldom pretty. Text especially
tends to become hard to read, and everything gets a bit fuzzy.
The old fashioned Cathode Ray Tube on the other hand functions
as more of a projector. A "Light gun" at the back of
the 'tube hurls a pattern of electrons forward, causing little
specs of phosphorus on the inside of the glass to light up and
create the image. This gives it a great deal of flexibility when
it comes to input resolution. So long as the resolution is lower
than the number of openings in the front of the glass (Called
the mask,) you'll end up with a nice looking picture. And even
when the resolution exceeds that limit the results are usually
okay, the image just loses fine detail. This makes a CRT monitor
ideal for playing old games on, watching home movies or any number
of videos which would become chunky and awful on a fancy new high
definition LCD TV. And with the price so low, they're great for
giving to the kids.
There's a slight snag though. Remember what I said about the
separate Chroma and Luma connectors? At the time it was an amazing
thing to see, but these days you won't find anything that outputs
s-video via two RCA cables. I've seen people make adapters from
the standard 4 pin s-video plug to 2 RCA connectors, but I think
I have a better solution.
Bam! S-video input. All it takes is a "borrowed" s-video
connector, 4 wires, some glue and a way to drill the hole.
It's as simple on the inside as it is on the outside. Just 4
wires from the jack to the Chroma and the Luma connectors brings
the 1702 one step closer to the modern age.
How does it work? Like a dream. The picture is even sharper and
clearer than before. I've got 3 of these monitors at the moment
and they've all been modified like this. It's so easy and the
improvement so large that there's no reason not to.
If there's any interest I'll record a video walkthrough the next
time I modify one of these.
