The author had fun building homebrew batteries to power a radio transmitter using natural power sources. They started with lemon batteries, common in school science projects, commonly believed to produce 0.5V and 1mA. The results, however, were disappointing, with only 0.3uW of power produced from a lemon battery across a 10k load. The author experimented with different materials, and found that bleach worked much better than lemon juice, producing ten times the power. They even connected four bleach cells to power a 40m transmitter successfully. Further experiments included salt and vinegar cells, with varying levels of success. Overall, the homemade battery experiments yielded surprising results, challenging traditional views on power generation.
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