A RGB and audio amp for your PC Engine and friends (Core Grafx, Turbo Grafx and whatnot). Mega Drive 2 compatible video plug, RGB SCART cable should have 75Ohm resistors (and preferably also 220uF caps) which the cables should have already. Audio is also amplified a little to get higher volume, as it is a bit low from the expansion port.

• U1 3x23 Pin 2.54mm pitch header. Samtec SSQ-123-02-T-T-RA, SSW-123-02-T-T-RA (or -F-T-RA versions). As such only the left 2x3 pins and the right 3x3 pins are connected, thus any combination of plugs that covers those are adequate. 3xSSW-102-02-T-T-RA should thus also be good, or 2xSSW-103-02-T-T-RA. Note that Samtecs portfolio is huge, and there are many combinations of plugs that will work as long as they have 2.54 mm/0.100" pitch, are triple row and right angle.
• U3 MINI-DIN-9PIN (I used MDC-209 from tme.eu, but MD-90S from Mouser should be just as good)
• C1,C2,C3,C4 0.1uF 0805 MLCC SMD capacitor
• J1 1x02 Pin 2.54mm pitch connector (not necessary if you dont wanna disable the filter)
• R1,R3,R4,R5,R6,R11,R12 10K 0805 SMD resistor
• U2 THS7374 video amp
• C6,C7 2.2uF 0805 MLCC SMD capacitor
• C10,C11 1uF 0805 MLCC SMD capacitor
• R7,R8 1M 0805 SMD resistor
• R9,R10 2K7 0805 SMD resistor
• U4 TS922A opamp SOIC-8
• C5 10uF 0805 MLCC SMD capacitor
• C8,C9 10nF Film capacitor THT L7.2mm, W2.5mm, P5.00mm
• C12,C13 10uF electrolytic SMD capacitor 5x5.3
• R2 75R 0805 SMD resistor

Capacitors should be rated for 16V or higher (lower should also work, no voltages should exceed the 5V).

I recommend to 3D print one of these brackets to provide a mechanical stabilization of the card when used in PC Engine or Core Grafx: https://www.thingiverse.com/thing:3245238

I don’t have a TG16 to measure the port and make a similar for that.

Revision B of this whose sole purpose is the two notches in the side to allow for a small 3D printable case. You can find the case here

Small changes in the routing also, should make no real difference.