Silly Wins
I feel a little silly celebrating this - but a win's a win. Always celebrate a win.
I have a small portable stereo, which until this morning relied 100% on an electrical outlet. Earlier this year I tried using some spare "D" batteries I had lying around for a different purpose that also didn't work, but to no avail. The stereo wouldn't operate on battery power. I set it aside.
Cut to: this morning, I had the stereo upstairs with me in the office. I randomly noticed a small switch on the side: "AC/DC". I grabbed those batteries and popped them into the stereo, flipped the switch, and - success! We have power.
So now this stereo is truly portable and a lot easier to move from room-to-room as needed.