Jaguar:Reverse Polarity Protection Diode

The Atari Jaguar and CD addon both lack protection from reverse polarity. If you are servicing a Jaguar, you may want to perform this quick mod to protect the Jaguar from ever having the wrong power supply plugged in and frying the power regulator, two capacitors, and a resistor.

Atari Jaguar

You will need a 1N5400 (protection up to 3A) rectifier diode. You can also use a higher voltage rated diode.

1. Desolder the wire that connects a ferrite filter to the positive pin on the side of power supply terminal. Some Jaguar revisions have different wire colors, so the wire may be be black, red, or white. Pay close attention to the location of the wire in the photo below, not its color!

   

2. Solder a diode to the (now empty) trace where the filter wire connected. The bar or line on your diode denoting the cathode (negative) side should face up and the anode (positive) side should be soldered to the PCB.

   Black and white variant:
   

   Black and red variant:
   

3. Solder the filter wire to the cathode side of the diode with the bar. Clean any flux left on the PCB with isopropyl alcohol.

If you soldered the diode backwards, the console won’t power on.