While the GoPro HERO is nice and small, a consequence of this small size is poor battery life. Battery backpacks can help extend the run-time. However, they can be finicky and do not add that much to the device run-time. Another solution is using a power cable. Preferably, one that plugs into the HERO port so that a case can be used.
The Cable
Several manufactures sell cables that plug into the HERO port. While some cables include a backpack backdoor, reviews complained of improper sealing with the GoPro case. Hence, I opted to purchase a cable and modify a backback backdoor.
I ended up purchasing CamDo Solutions’ ABE04 Battery Eliminator. The ABE04 is a USB cable that plugs into the HERO port, just like the battery backpack. Near the HERO plug, it has a small black plastic box that contains a switching regulator (likely a buck regulator for providing ~4V to the VBat supply pins of the HERO plug).
The Solution
Since the intended use of this power cable is in a dusty, and possibly wet environment, leaving the back of the GoPro case open is not an option. Luckily, the backpack backdoor is very close to the perfect size to hold the switching regulator. Additionally, by removing the push-button on the side, the USB power cable can be snaked into the case.
Removing the push-button was easy. A little retention clip held the spring-loaded sealing assembly together. A needle nose pliers made quick work of that. Unfortunately, the push-button hole was just a little too small to fit the 3.41mm diameter cable through. Using a drill, the hole was expanded so that the cable could fit through.
The cable itself needed to be de-soldered from the PCB so that it could be routed through the hole. And, once the USB power cable was routed through the hole, the wires had to be soldered back onto the PCB. This was not much of a problem. The last steps involved using hot glue to reassemble the black box, mount it onto the backdoor, and securing the USB cable.
After mounting the power module to the case, it was time to connect and install a GoPro into the case. With the connector plugged into the HERO port, there is just enough room to fit the GoPro and connector into the case. To make the fit easier, the extra rubber grommet around the cable was remove to enhance its flexibility. Ideally, a custom, lower profile HERO port connector would be used.
Ultimately, the mod serves its purpose; it adds a little bulk with the promise of infinite run time. While the connector is a little large, resulting in a very tight fit, everything does fit. A straight forward improvement to cut down on the bulk would be to use a standard housing rather than a diving housing. And, should I need a second USB powered housing, I will start with the standard housing for this very reason.
-John Havlik
[end of transmission, stay tuned]