This is a solar panel battery charger schematic for AA and AAA rechargeable batteries. A small solar panel would be very good as a source of voltage charger. Building a solar AA battery charger only requires a few components and a simple construction.
Solar panels should be well adapted to the battery to be charged or the battery may be overcharged. If you want to charge batteries with different capacities, then you need to change the solar panels.
Since this is a simple solar battery charger that does not automatically turn off when the battery is full. So we need to maintain the charging current is low enough that will not damage the battery even when they are fully charged.
An LM317T voltage regulator chip that can be used with a suitable resistor to regulate current. See solar AA battery charger
Build Accurate LC Meter and start making your own coils and inductors. This LC Meter allows to measure incredibly small inductances making it perfect tool for making all types of RF coils. LC Meter can measure inductances starting from 10nH - 1000nH, 1uH - 1000uH, 1mH - 100mH and capacitances from 0.1pF up to 900nF. The circuit includes an auto ranging and reset function to make sure the readings are as accurate as possible ... [more]