Template for ColecoVision YPbPr/Component video modification:
Tape the template on the back of the top piece of the ColecoVision case. The template should fit the casing vertically, ignoring the small ledge at the bottom.
The holes should be as high as possible, but low enough to accommodate the “L” brackets inside (as mentioned, the template should match the case).
If the holes are drilled too high, the “L” brackets won’t fit properly. If this happens, you can carefully file down the “L” brackets to fit.
If the holes are drilled too low, the PCB will interfere too much with the top shielding. If this happens, the top shielding will need to be cut or removed. If the shielding is cut, put electrical tape on the cut edge, to cover any sharp edges.
If the holes are drilled in the proper location (or not), the top shielding will still likely be very close or touching the modification board. Electrical tape needs to be taped to the top shielding, to make sure no shorting takes place. Use several layers, to make sure the solder points won’t poke through. Tape the whole length of the shielding, and double the width, so the whole back 1.5” is covered.
Bolt hole diameter: ~1/8”
RCA hole diameter: ~3/8” to ~13/32”
Trimmer hole diameter: ~1/8” (optional)
Slightly larger hole sizes should be acceptable – Note that the RCA holes need to be able to accommodate the ground “ring” on the RCA cable you are using, because of the thickness of the ColecoVision walls.