These 2 stabilized power packs are designed to replace the 3 volts and 9v-0-9v batteries which provide power to the operational amplifier in Experiment 17.
Batteries tend to run down after sometime and therefore the students do not obtain reliable and consistent results.
Furthermore, these 2 power packs have built-in electronic short-circuit and overload protection. When a short-circuit occurs, the l.e.d turns off and comes on again when the cause of the short-circuit is removed.
