Just got a Jap dreamcast...

hey everbody! I just picked up a jap dreamcast for £30 (no bad!) I want to ask a few questions about it. It has a removable plastic bit where the modem should be, anyone know what that is? And how do I recharge the battery?
The purpose of a terminator is to stop certain anomalies from occuring in transmission. This has to do with providing a connection to ground with an impedance matched to the characteristic impedance of the bus. I've been told that this is essentially the same thing as making the transmission line infinitely long from a transmission theory standpoint. I've never studied transmission theory so I don't really understand how this works. Presumably the modem and BBA terminate the bus also.
It keeps signals on the expansion bus from bouncing around. :)

Sorry, I have a bad habit of getting needlessly detailed.
the battery recharges by leaving it plugged in and switched on for a while

i think it supposedly loses its memory after 20 days of not being switched on, although even if it does its only the clock settings and your preferences in the setup that are lost anyway
Right! Thanks guys. One more question, when I'm playing Soul Caliber (Jap) the DC makes a constant clicking noise whilst reading the game music. Is this normal? (The music plays fine)
yes, that's "normal".. bad coding on Namco's part. it's basically streaming the audio in an ugly way.