Adam looks at why the 13V rail appearing on the Yaesu G-5500’s External Control connector drops so much when a Rotator Controller board and 5.0″ Nextion are powered off this rail.

The rear of the Yaesu controller has an ‘External Control’ port, intended to connect to a computer interface.

 

 

The 13V rail for powering external equipment is only rated to 200 mA, and even then you can expect the rail to drop to 6V.

 

However, inside we find the transformer secondary winding is actually rated to 1.7 amps.

 

So how can we power external equipment, like a rotator controller with a 5.0″ Nextion touchscreen that requires more than 200mA?

The fix is very easy to perform, as shown in this video.