ColecoVision Composite Mod

 

So this past week I finally decided to play around with the ColecoVision that I’ve had in the closet for the past 20 years or so.  I can play my ColecoVision games on my MiSTer Multisystem, but there’s nothing quite like the original hardware experience – especially the controllers, in this case.

The issue, of course, is that the ColecoVision only has RF output, as was used by the antennae connections of televisions at the time.  To get the system to connect to a new monitor, you need to  modify the console to add either composite or RGB outputs.

I went with composite, via the Console5 mod kit, though the output is not as good as RGB.  To the right you can see the competed composite board.

The board is DIY – it does not come populated.  It’s very tiny and all components are SMD, so hopefully you have an iron with a small tip.  I used my Pinecil for most of the components, and it worked great.

C1 and C3 only have pads on the bottom, so it will go a bit easier if you have a hot air station to reflow those components into place.

To the left you can see the TRRS barrel connector I decided to use instead of individual video and sound outputs.  I wanted to minimize cutting holes in the plastic shell, and this allows me to connect it with a single cable like those used on old-style camcorders.

The barrel connectors pins are numbered and correspond to 1 = Red, 2 = White, 3 = Yellow, 4 = Ground.

Note: Though the instructions tell you to use the 10uF smoothing cap to connect the sound output to the RF box, but connecting it to the left leg of C33 (right next to the RF modulator) works better (it’s closer to your output if you’re adding the jack to the right side of the case) and doesn’t require the use of the capacitor.

In fact, the only connection you’ll want to connect in the modulator is the video connection, and it’s much easier to connect to the solder point to the left of the one they show in their diagram.

Ground can be found on the board just left of the BIOS chip, and VCC can be pulled from the right edge of WJ2. Those two points will probably be much closer to where you sit the mod chip, and it makes it easier for you to snake the one video wire out of the modulator housing so that you don’t need to trim any of the metal from the housing.

One thing I did have to trim was the RF shielding that covers the entire motherboard. But, I just cut off a small rectangle in the back so that the output jack and wires could make it through. Be sure to take a file to the edges after you snip it or else its sharp-as-a knife edging could cut through your wires and ground something out.