Press and hold the Menu and Center buttons for a few seconds until the apple shows on the screen and lights up. (top of scroll wheel and center button).
If it continually shows an apple but doesn’t quite light up, your battery is probably flat. This is good! Just recharge for awhile and consider trying a dedicated power adapter instead of a USB port. This has happened to me more than once where the USB port could not supply enough power to charge the ipod.
Yes, 1/4 Terabyte in my hand
This drive fits in the ipod classic, both physically and electrically with no modifications:
Item Title:Toshiba 240GB 1.8″ Hard Drive MK2431GAH
PS. This was a forced upgrade because the ipod dropped and the drive crashed. Another example of a perceived “problem” becoming an “opportunity”
I love the ipod classic because I can run it in my pocket and while driving, it doesn’t require your eyeball attention. In this case I put a stick on dot in the middle of the scroll wheel, so I can feel my way around and run the unit without looking. Handheld touch screen devices can be a disadvantage and a safety concern if you like to listen to music and books while driving.