A few month ago my daughter got a present for "Sinterklaas": a small battery powered game (3 x 1.5Volt AA-batteries). It turned out to be a battery eating device. After a couple of "refills" I took a voltmeter to see whether the batteries were really empty. Guess what: we measured a voltage of approx. 1 Volt. So there was still a lot of energy left to get wasted.
So I decided to build a batery discharger to get the voltage down a little.
Below: Irina showing off with the first design of the discharger.
A closer look:
a shoe box a peace of wood 4 nails an on/off switch a 5mm yellow LED some wire.
A few days ago I found on old battery charger. Advantages: smaller and it has been designed for holding batteries.
First I removed all resistors, diodes, the cable and the trafo. Then I rewired it for discharging batteries.
A minor improvement: use the quick/normal charge switch as an on/off switch.
And here she is: the final version...
Nice light effects at night...
And of course we had a lot of fun and laughter...