My JVC GRD72 miniDV camcorder will no longer run off battery power after
I *ahem* *coughcough* snagged the power cable and knocked it off the
table where it was charging. It landed on soft carpet and still
works--I've operated it for more than an hour total time afterward, both
recording and playback--but it will only run while plugged in, even
though the battery was fully charged at the time of the accident.

I suspect that the AC adapter socket was damaged in such a way that it
thinks the adapter is always plugged in, even when it isn't, and that's
why it refuses to switch to battery power. Does that sound reasonable?

Or is it possible that the battery itself was broken in the fall? I
measured 7.55V across its '+' and '-' terminals (the rated voltage is
7.2V), but I don't know how to test the 'T' terminal, which is
presumably a charge sensor.

Any advice would be appreciated.