Model 2 Triple Bypass Troubleshooting

[Released: 1988] The Sega Genesis was Sega's most successful console; though Sega has never released a total sales figure quote. Several add-ons were created including the Sega CD and Sega 32X which extended its capabilities.

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Model 2 Triple Bypass Troubleshooting

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[url=https://imgur.com/gallery/WTVhdfp]Photos[/URL] Tl;dr, I’m getting no video out of my Genesis model 2 VA1 after installing a triple bypass mod. When I power the console on, the LED goes on and I can hear an audible “popâ€￾ sound in both stereo channels but the game does not boot and there is no video output. I recapped the console before installing the mod with a kit from Console 5. I checked continuity between the 3BP board and the video DIN and all pins checked out. My RGB lines also checked out. Sync from pin 10 of the video chip also checked out. I’m pulling 5v directly from the regulator, and that also checked out. Checking the voltages of the DIN pins went as follows:
pin 1 (B) .306v pin 2 (5v) 4.9v pin 3 (G) .320 pin 4 (originally composite video) .277v pin 5 (sync) 3.67v pin 6 (mono audio, disconnected) 0v pin 7 (R) .284v pin 8 (l audio) starts at 1.63v and then goes downward pin 9 (r audio) starts at 1.65v then goes downward
With these on the regulator: O on the regulator: 4.9v, I on the regulator: 11.18v.
In terms of work done, I removed all of the components as recommended in the Mega Amp installation guide except for R21. Because of this, the D jumper on the 3BP board is left open. I also removed CE12 and the three EMs near the DIN to sever composite video, mono audio, and 5v power. R48 was removed as I heard it could improve C-sync. The RGB pins are lifted from the video chip to sever them from the DIN. The RGB lines to the 3BP board have the recommended 5.6k pull up resistors on each line. All of the audio lines are soldered to (what I can only assume based on a couple of installation guides) the correct pads. I don’t have 32x, Sega CD, or power base converter to test their audio. If any of you see anything incorrect or missing in my photos, please tell me. Beyond that I can only assume that there is a short going on somewhere, or either a capacitor from the Console 5 kit or the 3BP board itself is dead. I have cleaned the PCB and cartridge slot with contact cleaner and a brush a number of times, so I don’t think it’s related to dust or grime at all. Grateful for any tips or suggestions.

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