When I plugged the GPS into the scanner with a conversion cable the GPS was not powered. When I plug the GPS into a USB power source it powered up.
I'm planning on no power at the port, and charging the scanner when I have the GPS plugged in.
The scanner USB port does NOT supply power, so you will have to have a Y-cable that goes between the scanner the GPS, and a USB power source.
Also, the USB version of the puck won't work. The only version that will work without extra conversion circuitry is the BR-355S4. The connection between the USB converter and the BU puck is TTL, not RS232.