Sega 32X Auto Hertz Switchless Region Mod Install Guide

A 32X is a region locked console add-on that will only work with a Mega Drive of the same region. Because of this it is necessary to region mod both the 32X and Mega Drive for full compatibility with games and to also play them in 60Hz.

The 32X Auto Hertz Switchless Region Mod will make the 32X fully region free and allow it to attach to any region of Mega Drive and run any region of game. It works by detecting the Vsync from the Mega Drive cartridge port and using it to control the video refresh rate of the 32X automatically. The region of both the 32X and Mega Drive is then controlled by the Mega Drive region mod.

Installation is very simple and only requires soldering four wires and modifying the plastic brace for the cartridge port.

Mod Pinout

Solder Map

Prepare the Mainboard

Add some solder to the four main solder points.

  • Pin 1 +5V. This point is a little small and can be enlarged (it is not required) by scraping away some of the adjacent solder mask to expose more of the copper track for soldering. Use the tip of a scalpel to carefully scrape away the solder mask whilst viewed under magnification for best results.

  • Pin 5 TTL VSync Detecting. Pin B13 from the right side of the cartridge port.
  • Pin 6 50/60Hz video rate switching.
  • Pin 8 Ground. This point will require some additional heat to get the solder to flow as it is attached to a large ground plane.
  • Stick down the chip so Pin1 +5V is facing towards the front of the board where the Sega copyright text is located and Pin 5 TTL Vsync, Pin 6 50/60Hz Video Rate, & Pin 8 Ground are facing towards back of the board where the output DIN is located.

Cartridge Port Brace Cut

It is necessary to cut a rout out of the cartridge port brace for the Pin 5 TTL Vsync wire. Failing to do this cut will prevent the 32X main board from sitting flush inside the case which can cause stress to the board, and potentially crush the wire and cause unreliable operation.

Because of this, ensure that the wire for Pin 5 TTL VSync comes off the cartridge port Pin B13 at a 90 degree angle and is sufficiently long enough to not get trapped by the cartridge port brace when routed to the chip.

A tunnel for the wire can be achieved with a electric rotary tool or a pair of side-cutters.

When putting the 32X back together it is important to make sure that this cartridge port wire does not end up between the brace and the 32X main board (notice the blue wire running close to the brace).


Vsync can be taken from cartridge slot pin B13 or CN4 pin 15.