Sega Mega Drive Dual Frequency Oscillator Install Guide

This guide will show you how to install a Dual Frequency Oscillator into a Sega Mega Drive.

When region modding a Mega Drive the console will run at an out of spec video refresh rate when using the forced region. The Dual Frequency Oscillator corrects this by changing the oscillator frequency to the correct one depending on what region is selected.

The Sega Mega Drive model 1 has a pair of jumpers called JP3/JP4 which are connected up to the PAL/NTSC selector pin of both the CXA1145P (Pin 7) and the SEGA 315-3513A VDP (Pin 52).

To be continued.