Hello, and welcome back. This episode is in many ways a follow up to an episode I did
back in October on my other channel, 8-Bit Keys.
In that video, I was going to show you how the musical keyboard on the Intellivision
worked, and then I was going to do a composite mod and show you some other things. Well,
I ended up spending all of the time on that video doing a repair on the keyboard mechanism,
so I never got around to the composite mod.
Also, shortly after that video was released, I went to the Portland Retro Gaming expo.
And literally the last day I was there as I was packing up and getting ready to go,
William Moeller comes over to me and donates two Intellivision games. These are sort of
special because they are older games from the late 1980s, but they were never released
on the Intellivision. And so these are modern recreations of those games for the Intellivision
console. The first one here is Defender of the Crown, which is actually licensed by Cinemaware.
And the second one is Jeff Minter’s Hover Bovver, which is licensed by Llamasoft.
So, in order to show these, I really need a proper composite output on my Intellivision.
In fact, the 3 main reasons you would want to modify any console like this to have a
composite output would be, number 1 for better video quality. Although it varies from one
to the next exactly how much better it will be. Second thing is, more display options.
It’s getting harder and harder to find good televisions that have that sort of RF connection,
plus there are all kinds of monitors that can display composite but not RF. And the
last reason, sort of ties in with that, which is easier to capture video. So yeah, for me
I need to be able to connect these consoles to a video capture device, and generally that
means it needs composite. Sure, you can use a VCR or some other type of demodulator, but
that reduces the quality and just adds a lot of extra work and complexity.
So, why does composite look better than RF? Well, this is television static. Some people
say this static is caused by cosmic background radiation left over from the Big Bang. Other
say it is just because when no signal is present, the gain gets turned to maximum, amplifying
any noise that is inherently in the receiver circuit. Either way around, even when a signal
is present, there is always some noise on an RF signal. It is most noticeable when looking
at something that is supposed to be a solid color. Now, the Intellivision has a surprisingly
sharp RF output compared to some systems I’ve used. But, it still has some minor noise.
If you look at the black areas, these look really clear. But if you look at solid colors
like the water, you can see the noise. In a traditional television broadcast, these
sort of solid colors wouldn’t be expected in a live image. Anyway, we’ll come back
and compare to this footage when we’re done.
So here’s the Intellivision 2. It’s just like the original Intellivision only it’s
smaller and cost reduced, but runs the same games. On the rear, we’ve got the power
port, channel selector, and of course RF output. So, ideally, I’d like to replace that with
a composite video and separate audio jack.
Disassembly is really easy on this version unlike the original which is a total pain
in the rear. After you remove the controllers there are just two screws on the bottom of
the console, and there you go.
The first thing we’ll do is have a look at the chips, like we always do on this channel.
This first one is the sound chip, which isn’t hard to spot because it has the word SOUND
printed right on it. It’s also the same chip we were originally using in the Commander
X16.
These next two chips here are ROM chips.
This one is the video chip. It looks blank in this photo, but if you hold it just right
in the light, you can see the numbers on it.
Up here, this is the CPU. And this last large chip here, actually is totally blank. There
are no visible numbers on mine at all. I was only able to figure out what it was by digging
up the schematic. Anyway, yeah, this chip is kind of weird. It’s a combination of
an I/O controller chip and also contains around 700 bytes of RAM.
This little chip here is called the color processor. And then we have 4 different RAM
chips.
And so that’s the board, but the main thing we’re going to be interested in is this
RF-modulator. This little box is what takes the signals and converts them to RF.
In fact, if you look at the side of it, you’ll see 4 wires coming out. Of course, there’s
really 5 connections. The chassis itself acts as ground and solders straight to the board.
This wire here is the video signal, and next to that is 12V power source for the modulator,
which we won’t need for our hack. Next is the audio signal. And finally is the channel
selector, which we also won’t need for our hack.
Looking online, it wasn’t hard to find a schematic of the circuit I needed to make
to do this modification. I asked my friend Kevin over at TexElec if he could whip something
together for me real quick, and this is what he made.
So, my plan is, to actually remove the modulator and mount something in its place. The modulator
appears to be soldered in with 4 really large connections. So, I got to work with some desoldering
braid to soak up all of this extra solder. Then I just needed to bend these little pieces
back out of the way. And it came off really easily. And here it is. I won’t be needing
this this anymore…. Or will I?
When I connected the board and powered it up, I couldn’t get a proper video signal.
Sometimes I got crazy stuff like this, but most of the time I got nothing at all, just
a black screen.
Kevin and I went back and forth for a couple of days trying to figure out if there was
something wrong with the circuit that he’d built, and one of the things that we figured
out when we started looking at other hacks that other people had done to their Intellivision,
we discovered that everyone who did the composite modification left their RF modulator in place.
So, I used some alligator clips and re-attached the video and 12V input of the modulator,
along with attaching to the ground plane like so, and to my amazement, when powering it
on it works perfectly!
And, while the quality difference is not amazing, it is indeed noticeable. Just for reference,
here’s one of the original test images I made, and you can compare it here with the
composite image we have now. And while there is an obvious difference in contrast and brightness,
I would like to point out some of the more subtle differences. For one, if you look in
this area, you can see a lot of noise. It’s easier to see in a live image because the
noise is constantly moving and changing. But you can still see it even in the still image.
And obviously, this noise is not present on the composite version. Also, if you look up
here you’ll see a bright spot on the water, this is a form of ghosting. And if you look
at the composite image on the right, you’ll see there is no ghosting. And while composite
is certainly not as good as S-video or RGB video, I’ll take it over RF any day.
So, it turns out I’m going to have to keep the RF modulator for this to work.
So, that’s sort of unfortunate because we can’t quite figure out what it is that the
RF modulator is doing to the signal that makes it work. The original plan was after I tested
this little board that Kevin constructed and made sure it worked, he was going to go back
and actually get a custom manufactured board that would be the exact same shape and size
of the RF modulator, so that you could basically desolder the RF modulator and then put the
new board right in its place. And it would have the same video output in the exact same
location and everything. So, that is what the original plan was, but I guess at least
until somebody can tell us what it is that we’re doing wrong, I guess that’s not
going to happen. So, I’m just going to have to push forward and make something work with
what I’ve got.
So, I guess what I’ll need to do is put this RF modulator back where I found it. It’s
a good thing I didn’t cut these wires, which I was tempted to do.
And now I’ll resolder these connections on the bottom.
And just to make sure the RF signal is still working, I’ll power it on right quick. Oddly
enough, it seems to be missing color. OK, actually its not missing, it’s just very
low saturation for some reason. I flipped the channel switch over to the other channel,
and it seems to look fine. Another bizarre quirk of using RF.
So, I tested it like this with alligator clips and it worked. So I went ahead and soldered
the wires and now you can see it working like that.
So this is just the shell, so there’s nothing in here. Another problem I’m trying to figure
out is where to put the actual outputs. Because, you know, it’s got these vents in the back
and it’s not really suitable for using a panel mount connector. Now, if we’d done
our custom board we were talking about, then the ports would be soldered to the board so
it wouldn’t be an issue. But, I’m kind of thinking I’m going to have to put them
right here. There’s actually nothing up here, so there’s some empty space, so yeah.
As usual, I always apply masking tape to the area so I can experiment with where I want
to put the holes. And I’m also going to go ahead and put the board back in the case,
that way I can test the clearance of whatever I’m adding. And yeah, I’m pretty sure
there is going to be space.
So, now I’ll drill some pilot holes. Once that is done, I can remove the tape as it
is no longer needed. And then I’ll follow that up with one of those Christmas tree bits.
Time for a test fit, and it looks like I’m in business.
I really wish I had a yellow RCA jack for composite, but I don't at the moment. So I'll
use red for video and black for audio. It would be trivial to change this out later
for the correct color.
OK, so I have to figure out somewhere to mount the little circuit board. I thought about
using some stand offs and drilling into the top of the RF modulator, but I don’t have
the necessary parts to do this so I’d have to order them. And I’m already several days
behind schedule on this video. So I’m going to cheap out and use double sided mounting
tape. It’s not ideal, and it may not last permanently, but it will work for now.
So, just a few extra solder connections to finish up. And now I’ll double check that
it is going to close up. And yeah, everything fits just fine. Time to screw it back together.
And now, it’s time to test the composite jack. For the moment I’ll use this burger
time cartridge. And yeah, everything seems to be working just fine.
So, now it’s time to take a look at these two brand new games for the Intellivision.
We’ll take a look at Defender of the Crown first. And yes, it even comes with the little
overlay for the Intellivision controller, which is something I always thought was kind
of innovative about the controller. It slides down in here like this, so you have custom
controls for each game. And here’s the cartridge, which looks pretty well-made.
Well, here goes. OK, it seems to be working. Well, the good news is, since we have composite
video now, I don’t have to show you this on the television, instead I can connect this
to my video capture device like so. That way, I can capture clear video and audio, which
I’ll use for the rest of the review.
I wasn’t sure what to expect from these games, being I have never been a huge Intellivision
fan and I know the graphics and sound are just barely better than the Atari 2600. Nevertheless,
it seems they did a pretty good job porting a game like this.
So, I’ll pick my character.
Oh look, mouse control on an Intellivision. Well, it’s not really a mouse, but close
enough. I’ll start with a raid so I can collect some cash. I have to admit, doing
this with the Intellivision controller is a total pain. While I said the controller
was innovative for the overlay, it still sucks for gameplay. Then I’ll move onto a joust.
I’ll be honest, I never spent much time playing this game on other platforms either,
so I’m by no means an expert. But yeah, the graphics and animation are not bad considering
the limitations of the platform.
OK, time to move on to Hover Bovver. Again, I’ll insert the little overlay. And here’s
the cartridge.
Jim won’t mind if I borrow his mower. Again, I think the hardest part for me is using the
Intellivision controller to play this game. It’s really terrible. But otherwise, the
game seems pretty true to the originals, which only previously existed on the Commodore 64
and the Atari 8-bit computers.
And that’s actually about it for this episode. I hope you guys found this interesting and
entertaining, and maybe somebody can find it useful. I’m not terribly proud of the
way I mounted the little board on top of the RF modulator, but its kind of one of those
things, I’m actually leaving out of town tomorrow so it was either get it done now,
or you might not see this video for another couple of weeks. So, anyway, it works and
maybe I’ll revisit it in the future. And maybe do a little bit better mounting job,
especially if we can, if anybody can tell us what we need to do to get rid of the RF
modulator. That would be ideal. So, anyway, stick around for the next episode and thanks
for watching!