This circuit was found in a 1958’s publication. It uses germanium transistor, availble that time. In series with the 910 ohm transistor, in the collector of each transistor, LEDs can be added. The circuit can be powered from 9 to 12 V supplies.
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This circuit was found in a 1958’s publication. It uses germanium transistor, availble that time. In series with the 910 ohm transistor, in the collector of each transistor, LEDs can be added. The circuit can be powered from 9 to 12 V supplies.