What I have done is I have a USB charing port installed on the panel. This is used to charge an iPhone or iPad in flight and is powered by the ship's batteries, of which there are two, plus solar charger.

On Monday, September 25, 2017 at 5:31:19 PM UTC-7, Roy B. wrote:
Friends:
I am looking for a supplemental power pack that is easily rechargeable, reasonably compact, and will run my Oudie for 5+ hours on a single charge. Any suggestions?
ROY