Things I Learned: Powering ham radios with a USB-C breakout board

Project TouCans can be powered by USB-C!

I've been wanting to try this since I learned that there are boards that can be connected to USB-C power supplies that can request different voltages and currents and—if successful—then power a ham radio at that voltage. Today, Project TouCans made it's first ever USB-C powered QSOs!

I used a board I purchased at Adafruit. The easiest way to select a voltage and/or current is to solder bridge jumpers and/or scalpel the default jumpers. Beware though, if your input power supply can't handle either your voltage or current request, you'll wind up at the next lowest voltage down the scale that the supply can support. So, for example, when I broke the default current jumper to ask for 3 Amperes, I went from a happy 15 V supply down to a a 5 V supply, because my laptop charger will not/cannot support 3 amps at 15 volts.

I wasn't sure the green board RockMite that makes up half of Project TouCans could support a 15 V supply because while the red board kits at qrpme.com state that they can handle 15 V, the green board manual sticks adamantly at a documented 14 V power supply limit. After asking on a RockMite forum, and poring over the schematics I reached a consensus. The rig should... survive. So, I gave it a try.

The rig did great! There were differences however. With a Dell laptop supply, the rig is more susceptible to AM interference from our local broadcast sports station. With the Imuto phone charger brick, the AM station goes away, but there's a little bit of hum from the brick's switching circuits. Neither of these extra sounds was loud enough to prevent the rig from making a QSO on each of its new power sources though!

Heres' what the power path to the keyer, and by extension the rig looks like now.

Assuming everything keeps working the way it is now, this is going to make camping trips a little more simple. This is awesome!

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