Originally posted by dtm
On the RT2 the bulbs are really just for indication. Some people say the bulbs for the mini maglite AAAx1 works. However when a friend tried this he found he could not get the green protective cap back on because the bulb was too tall! Just remove one of bulbs and buy six (or more!) of the same size rated for around 1.5v or less!
The discharge is done by those white resistors and there are no diodes on the RT2.
dtm- you are right on that the bulbs are there just for indication of cell contact, but for the diode part, double-check your resources, for one, if there weren't any diodes in the tray, the tray would pulls the cells below 0 volts. Second, I had to go into the tray because the fan wire broke off inside and I clearly remember seeing the diodes.