This kit has a single AA battery holder into which a battery can be placed, LEDs then illuminate to show the remaining capacity of the battery. The circuit uses a quad operational amplifier to provide a reference voltage and comparators to determine which LEDs should go on. This makes it a great kit for studying operational amplifiers.
Testing of the kit can be performed using an adjustable power supply, or with our circuit tester (consisting of an AA battery holder, variable resistor & crocodile clips) .

Requires x3 AA batteries, available separately.