French Secam Atari 2600 - Teardown and RGB mod

What the hell is this?

So Atari released the 2600 in France without actually bothering to install the correct colour replication for the SECAM TV standard.

This means that everyone in France grew up thinking the Atari only had 8 very bad colours, when actually it was just running in black and white mode all the time.

The reason for this seems to be cost saving as to give full colour support to the 2600 in SECAM would have involved building a custom TIA chip for what was a very small market.

The only bonus is that it is very easy to mod for RGB, the 2600 uses interpolation in PAL and NTSC to give it's colour pallet, if the video is unmodulated (as in the SECAM Atari) you only get 8 colours but you can just hook those signals to a simple D to A circuit:

If you want to RGB mod a PAL or NTSC you need to buy one of these boards (or design your own):

[intelDX]

those colors are discounting, they took the only advantage from 2600 the fantastic color pallet !

[jujuverpres]

Very instructive video (diagrams and logics)
Yours Faithfully

[ovalteen]

Building a circuit to translate either PAL or NTSC QAM color output from the TIA into a proper FM for SECAM is a bit trickier than you might think. If you wanted to do it digitally, you'd need gates with a propagation delay of <20ns to build a shift register that operates at maximum speed. Even with today's logic ICs, that's a challenge. The cheaper choice is to build an analog demodulator like the PAL or NTSC TV uses, but then you'd send the color difference signals into a VCO to get the FM that you need. And you'd still need most of the color sync circuitry that is on the 2600 SECAM board now.

So they punted and used the brightness outputs as RGB. So each output controls color AND brightness. That's how blue looks dark blue while green and yellow look like neon colors.

[bertcbgwn]

Why did you mount the din connector not on the inside of the case ?

[thegreatjonzini]

Reminds me of the bad old days of pc cga graphics ;)