Time to modify my old SEGA Master System II.
Being a PAL console it runs at 50hz which makes the game run at 25fps instead of 30fps. This causes a slow down in game and also makes the game have bigger boarders around the screen. My plan is to mod the console and be able to switch between 50hz and 60hz on the fly.
Here is the console I plan to mod:
I’ve stripped the console down so i can get to all the IC’s etc and perform the mod
I’ve ordered a 3 Pin ON/ON SPDT switch. I’m using SPDT so that there are no shorts when i switch over from 50hz to 60hz. I also plan to add a power LED using a 5v power source on the board. No real benefit to this apart from making it look pretty cool!
Switch arrived so it’s onward with the 60hz mod!
Here is the IC we are working with. You need to lift leg 57 so i went ahead and did that.
Next up i needed to make a hole to mount the switch, i chose to mount it at the rear so it looks fairly original still.
Time to solder and mount the switch
Checking cartridge clearance..
Tested it on my tv and it works a charm! the speed difference is quite big! also the actual game boarders are smaller giving you more of the game on screen. The switch works flawlessly on the fly in game.
LED finally arrived so time to fit!
Removal of power button
Cutting a hole in the center so light can penetrate through the plastic
Soldering wire to the 3mm 5v LED and applying heatshrink to avoid any shorts
I then cut a section of the side away as the cables need to protrude out from the side so the power switch on the mainboard can still enter the power button to be switched back and forth
Applied some glue to hold it in place
I then looked for a power source on the board, the voltage regulator was the obvious place to look and it does indeed supply 5 volts.
Soldered the wires to the pins on the 99240 voltage regulator
Tidied the cables up
Power on test
***Update on 2nd unit***
Just completed a second unit without the LED mod but with a voltage regulator change.