Originally Posted by tqn
So my understanding is that you replace one of the AA (or AAA) batteries with the special NextGen transmitter-shaped battery. Does that mean the NextGen transmitter itself is a battery? Is this battery rechargeable, or do you need to buy a new transmitter battery (which would be expensive given how quickly a Harmony sucks power)?
The transmitter is a two part item. The outer cap is the transmitter, and there is a battery that is approx 2/3 ther size of a normal AAA battery that skips up inside it. The unit comes with two batteries so that you can keep the spare battery inside the unit so that it is always fully charged.
I bought an additional spare battery for a total of three. I keep one in the unit (charging) at all times, and I have the other two in two identical Harmony remotes. One powers my basement theater and the other runs my family room system. The NextGen repeater controls my satellite box, my Popcorn Hour media player, and an HDMI switch so I can share the two media devices between the upstairs and downstairs systems.
As you mentioned, Harmony remotes slug back the batteries, and because the NextGen battery is smaller than the typical AAA, I find that it lasts about half as long as the other three batteries in the Harmony.
I have had this little extender for over a year, and I still cant believe how well it works.