User:ApolloBoy/Oscilloscope Readings

Me farting around with an analog scope

Composite Video Signals

For the three shots, I used the title screen of the game Hustle Chumy as a test.

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  From a Sega SC-3000, which uses a TMS9918 VDP. Composite video goes through a simple buffer circuit and then out from a 5-pin DIN connector.

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  From a Sega SG-1000, which also uses a TMS9918. I modded this console with a DC-coupled circuit based on the THS7314, and the resulting output is rather strong as shown in the scope.

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  From a Sega SG-1000 II which uses the Sega 315-5066 ASIC. Here, I tapped a test point labeled TP1 to get composite video out, which taps the video signal before it goes to the RF modulator. Looks OKish on a display but I think there's room for improvement here