Images in older posts are missing or have been replaced with girls and the question seems to come up often.
So I stole the image from another side.
Step 1: make sure your TE or GT is working fine. Recap as well, old cap will go bad and it will ruin the board.
Step 2: take out game, batteries, power cable, TV tuner, etc.
Step 3: take it apart to get the mainboard.
Step 4: Find the chip HuC6260 and locate the pin numbering (or count from pin 1)
double check you have the right pin!!Step 5: desolder and life all the pins as indicated in the picture.
Step 6: connect pin 19, 25, 29,32, and 39 to one wire, this will go to LCD module for better ground shielding.
Step 7: connect the remaining 4 pins to resistors. Tie the other end of resistor to one common point connected to the base of any basic NPN transistor
Step 8: solder collector of the transistor to 5v source.
Step 9: emitter is composite video, connect that to a 75 ohms (or 2x 150 ohms in parallel as 75 is not commonly found locally) and the other end of the resistor to LCD's video input
Step 10: Get power to LCD module. Check docs if it takes 5v or needs higher unregulated voltage.
Step 11: double, triple, and quadruple check everything to ensure there's no short, bridged solder, or any problem.
Power it on and hope for the best.
optional, if you got larger LCD rather than 2.5", you will need to modify the front shell. Most people usually can get up to 3.5" LCD while still keeping the entire gut inside the TE or GT. Larger LCD is possible but you'd need to make a custom shell or housing to hold the LCD.
Feeling adventurous? PSOne LCD, RGB connection, clamshell case (or flat like Nintendo 2DS), make it like a PC Engine LT for a lot less than $500.
I plan to get mine with 3.5" LCD and also to hack in the save SRAM. Tennokoe2 is cheap on eBay and it's just 2 chips that one needs to make it work, plus battery or fat capacitor save support for SRAM chip.
