My MP3 FM Transmitter setup
The yellow box is a old Power It/Charge It box refitted with 27 nimhs, a 12v socket which the 12v MP3 player is located is on the bottom. The small Kaide I use a 2.4v nominal "C" battery pack.
Although the 12v pack (actually 10.8v nominal) needs recharged about every 4 days or 5 days after heavy use, the radio with external non amplified speakers will go for many days without recharge.

Not extremely difficult to keep these charge via pv even with our short late fall/early winter days.
For interesting old radio shows,
http://otrrlibrary.org/
Tim
Although the 12v pack (actually 10.8v nominal) needs recharged about every 4 days or 5 days after heavy use, the radio with external non amplified speakers will go for many days without recharge.

Not extremely difficult to keep these charge via pv even with our short late fall/early winter days.
For interesting old radio shows,
http://otrrlibrary.org/
Tim

