Things I Learned: Sometimes Ham Radio Batteries Don't Charge Over USB-C

This has happened once before. I hooked up the USB-C charger to the Imuto power brick which is now basically inside Project TouCans, left it over night to charge, and nothing. I woke up to the resounding 60 cycle hum that is the Imuto's internal buck converter stepping up the available voltage of the unit.

Project TouCans Dry Docked and Charing—I hope.

As with most engineering mistakes, there's a a way around ever having this happen again, and as with most engineering mistakes, that way involves process. Interestingly, there are two processes to avoid the not-charging Imuto conundrum. The first way is more interesting, yet less effective:

Unplug the keyer power input, making sure to leave the TouCans power input plugged in.

You'll know this worked because you'll still hear the hum over the headphones.

Now, plug the charger into the keyer power output from the Imuto. (This particular power brick is nice this way, you can charge it while it's being used.
TouCans internal keyer will reboot. This is because the brick momentarily turns off power altogether.
If the hum goes away, the brick is charging.
If it doesn't, jiggle the power connector until it does.

I find it really cool that the charging current provides enough power to turn off the buck converter immediately!

Here's the much less labor intensive process:

Unplug TouCans and the Keyer from their power inputs.
Plug the charging cable into either of the, now exposed, output power ports from the Imuto brick.
Peel back a piece of tape above the notch in the battery pack rim—remember, the battery pack is a Progresso Soup can. Look for a blinking light inside the can. The Imuto brick power read-out blinks as it charges.

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