Tectoy Megadrive motherboard revisions

I meant the motherboard that's got the CXA1145, not the chip itself. The funny thing about all tehis motherboard revision stuff is that my Japanes TMSS VA6 Megadrive 1 outputs the worst audio and video of the three...

maybe are capacitors drying? Does the VA6 have this problem too?

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Originally Posted by kool kitty89

I saw this a while back but never commented. The CXA1145 is the video encoder and has nothing to do with sound quality AFIK. The CXA1145, MB3514, and Samsung KA295D are the 3 encoders used on model 2s (and MDIIIs probably). The former 2 are OK with the 1145 being brighter and blurrier and the 3514 being dark but sharp; either can be adapted for S-video; these 2 are also the only ones used on model 1 MD and Genesis units.
The Samsung one is the most common and by far the worst, blurry and distorted with no S-video capabilities.

I don't think there's any corresponding audio trend with the video encoders used.

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Note: there is a Sony CXA1645 in the MegaDrive III that's equivalent to a US VA4 Genesis 2. That system has no blurring or dark video.

Most video encoders have an audio amp in them, but those are used for the Mono sound. They have nothing to do with the bad sound quality, but rather the rest of the sound circuitry(the quad op-amps, in particular.

all of them got sound buffers, but I have only seen those being used in clones...