The Future Was 8 bit, and I used those boards for many conversions, include ZX81, TS1000, Spectrum, TV Pong games and of course more 2600s.
recent mod, I tried fitting a socket to the input side of the board and used a pre-wired 4 way cable for the connections.
The Future Was 8 bit.
I am going to show you how to use these to modify various Atari 2600 systems, but first I am going to cover a bit of the theory behind what parts should be removed and how to locate them. By all means skip to the relevant section below if you prefer.
TheoryThe circuit is basically the same throughout all the models of 2600 from the 'heavy' sixer through to the 2600 Junior. The part numbers and values do change, so don't blindly follow any guide which just lists part numbers.
- Black is a ground connection (available at various points around the board)
- Red is 5V. this can usually be tapped from the place where the variable inductor was
- White is the audio out, which can be tapped where the resistor was removed
- Yellow is the video out, which can be tapped from the other resistor position
The other thing which needs to be removed is the modulator itself, including the daughter board if one is fitted.
The following are examples of three common Atari 2600 PAL boards. If your board does not match any of those, you should be able to work out the appropriate parts by matching them up the the schematic above.
Atari 2600 "Woody" 6 switch PALThe first one is the "Woody" style 6 switch Atari 2600 VCS. This has two boards, one with the switches and the modulator on, and one inside a diecast box with all the interesting circuitry on.
The audio is tapped from the right hand side of R209, Video from the right of R216, 5V from the bottom of L201, and 0V from a pad to the side of C238.
Atari 2600 "Woody" 4 switch PAL
The four switch version has a similar case to the six switch, but inside there is a single board. Unlike all the others, this does not have the 4050 buffers in the video section, but does add a 555 timer reset circuit. Later boards reversed both of these changes.
The video section is on the bottom right of the board.
Here, the parts removed are R209, R207, Q201, L201 and the RF modulator. In this case, I connected the wires to the 5 pin header next to the modulator, but you could pick up the signals from the component pads as before if you prefer.
Place the board at a convenient point in the case. I don't have a case for this one (I use it for testing), so I mounted the board at the back where the channel switch would have been on NTSC models.
Atari 2600 Junior PAL
The 2600 Jr is also a single board construction, with all the interesting bits under a metal screen.
With that removed, it has a similar layout to the 4 switch board.
The video parts are again bottom right of the board.
The parts to be removed are Q4, L8, R48, R56 and the modulator.
This time, I connected the wires on the bottom of the board, and soldered to the points shown.
The wires all go through a hole that was under the modulator.
The video buffer board can then be fitted where the phono connector was for the original TV out, raised up on a couple of foam pads.
This gives a neat mod and doesn't interfere when the screen is replaced.
The 3.5mm jack cable can now be plugged in where the old video lead would have plugged in, with no modification to the case required.
All back together, and time for some more testing I think.
Oh, I suppose I should put in a screenshot.
Looks good to me.