Charging Hidden Batteries Using the MakerHawk USB Multimeter

Soon, I'll get the bandwidth to document Project TouCans entire power supply system. For now, suffice it to say that, like the rest of TouCans, it is non-standard.

One of the non-standard issues we run into is that while there's a USB-C cable accessible outside TouCans for charging the internal batter pack, the battery pack's charging indicator is hidden inside of TouCans in its optional batter pack housed in an empty can of Progresso tomato soup. Consequently, we've occasionally not charged the batteries because the USB-C connection was unhappy. Enter the MakerHawk multimeter.

The meter acts as a USB-C female to female adapter, which frankly we needed. It also ships with a USB-C female-to-female barrel, I'm not sure why yet. We haven't used it. When we plug the radio in to charge, we plug the charger into one side of the meter and the internal battery pack's charging cable to the other.

When the cables are plugged in correctly, (sometimes we have to flip the wall charger cable over), the meter shows the voltage of the charger and current being drawn by the battery.

When the battery is fully charged, the current reading falls to zero.

Word on the forums is that the multimeter can download a graph of charging current vs. time, at least with the Bluetooth enabled version I dont' think we have. I've made no effort to find out if our multimeter enables charging data to be downloaded.

It's an extra piece of kit to cart around, but it's worth it for knowing for certain when the battery's charged. And yeah, I know, what Project TouCans really needed was thing that looked like a timer to go with the coils of wire and tape it's already got :)

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