DATAMATH PICTURES

This original TI-2500B uses either
3 rechargeable AA-size cells or
4 alkaline cells. A small switch
(under lower cells) selects the
charging/ non-charging mode.

The first production batch of the
TI-2500B manufactured in Spain
kept the switch.

© Phillipe Leckler

This TI-2500B manufactured in
Spain misses one battery place
and the switch in the battery
compartment.
© Gordon Dyer

This TI-2510 uses 4 AA-sized
alkaline or carbon-zinc batteries.
The switch in the battery compartment is missing, too.

This TI-2511 uses 4 AA-sized
alkaline or carbon-zinc batteries.
The switch in the battery compartment is missing, too.