I have a little CD/radio boombox which is all right for the price-plays
well and uses either AC or batteries, and has a red-backlit display for
the CD.
The only problem with this boombox is that on batteries, when they
die, they just "pphhhhht" go dead. Bam. with absolutely no warning.
It
doesn't start to sound "static-y". The CD playback doesn't slow
down or begin to skip. The volume doesn't cut out, the lights don't
flicker, nothing. The CD will literally just cut to nothing instantly,
and therafter just show a flashing line forever, and even then, the
display doesn't dim or flicker, so it appears that the CD is dirty or
worn out. The radio will similarly cut out-it just turns to fuzz in a
second. Even the instruction book doesn't mention the boombox
instantly going belly-up- it says "when the radio sound becomes poor
or CD playback becomes unstable, the batteries need to be replaced"
I cannot have extra batteries on hand for this thing because it takes
8 C batteries (!!!!!) and I use rechargeable batteries, and I simply
don't have enough to run this thing more than once-even if I raid
from absolutely every other C-battery device I own, I still don't have
enough to have an extra set of batteries. I don't use this thing on
batteries quite often enough to justify buying more rechargeable
batteries for it.
I propose a small rechargeable battery that is behind it's own
independent cover, being charged by the main batteries during use,
but not actually on active duty normally. This will be a somewhat
common type that is used in many cordless phones. Not enough to
run the boombox on it's own, but that's not the point.
It will be enough to run the boombox in conjuction with dying main
batteries, maybe it could power the CD spinner and/or laser to take
some of the load off of the main batteries, which would then be able
to just run the speakers or whatever. The "kick-start" battery is only
on-duty when a specific switch is pushed, which would also turn off
the display backlight. There will be some sort of internal regulator
which will prevent the kick-start battery from causing an over-
voltage if the switch is unnecessarily pushed.
I believe that a hand-crank mechanism would be too "unstable" of a
power source for something like a boombox because if you speed or
slow your cranking-even momentarily, it may cut in and out and
probably wouldn't be good for the boombox. Also, the cranking
motion would probably cause the CD to skip
Why not just keep it on-line all the time? Well, if you had to
manually activate this function, it would also function as a crude
"low battery" warning.
Here's how it would look to the user- The boombox stops working.
They push the kick-start button, and then the boombox continues to
function for a little while longer. Since the main batteries are now
powering fewer things at once, they may actually last longer under
the same operating conditions.