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I have an old Philips Videopac C52 video game console of the  Philips Odyssey 2 family like the G-7000 with 128-byte RAM:

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While checking its boards to compare with the schematics I got for the G-7000 I found that the PAL encoder (The C52 that I have is made in France) does not use a monolitic integrated circuit but it uses instead a transistor-based circuit that integrates both the PAL encoder and the RF modulator:

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In the G-7000 schematics the PAL decoder is annotated IC679 but the IC type is not indicated:

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I found on the internet a photo of the IC679 but could not read its type and maybe it is intentionally erased:

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What gets me to think that the video encoder might have been a critical component is that even in the G-7000 there is an option to either use the IC or extend the board to use an external circuit for the encoder:

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My question is:

Was the PAL/NTSC video encoder IC a critical component (cost-wise, availability...) in early video game consoles like RAM for early microcomputers? What was the IC679?

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    The C52 was a french market version of the G-7000. France didn't use PAL, they used SECAM, so that might be the answer for not using a PAL colour decoder chip.
    – UncleBod
    Mar 5, 2021 at 9:16
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    How would the PAL encoder could be a bottleneck and for what, since that is what you ask? For the second question, on IC679 it reads 612160-3 and seems to have manufacturer logo of EXAR. And true, that would not be a PAL but a SECAM model which explains not having a PAL encoder.
    – Justme
    Mar 5, 2021 at 9:51
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    It's not entirely clear what you mean by "bottleneck", as I don't understand how the ordinary meaning of the term (part of a system that has the lowest performance, thus limiting the entire system to that level of performance) applies in this situation. Can you explain what would be limited by said IC that could be higher performance otherwise?
    – occipita
    Mar 5, 2021 at 10:35
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    @PaulGhobril PAL, like NTSC or SECAM encoding isn't a huge task, and can be done with a reasonable number of analogue components. Especially if all signal components are already delivered in an appropriate way. While using a chip is a cost reduction measure, it's not a big one in itself, but mostly for board production thru less components to be drilled and placed. Other than that Justme's Answer covers everything about this particular case.
    – Raffzahn
    Mar 5, 2021 at 15:25
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    @Raffzahn you make a great point, but integration has driven technology development throughout history, this is an example of integration, you package and optimize a technology for broader use. Not every company wants to or has the ability to hire a team to validate a discrete design and integration turns that piece into something reusable, It also, therefore, removes duplication of effort, so integration is demanded by the market.
    – crasic
    Mar 5, 2021 at 17:30

1 Answer 1

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The PAL video encoder was not a bottleneck of any kind.

It is left out because the unit is not a PAL model, but a SECAM model, which needs a different kind of encoder. So the chip is not needed and it would be useless and just cause extra cost and power consumption in the SECAM model.

The necessary SECAM encoder is integrated to the separate board with the RF modulator.

The IC679 PAL encoder has EXAR logo and model number reads 612160-3.

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