Mini drill control (CB8767E)

This control for 12 V drills was found in a 90s Elektor. The components are current, and Q1 can be replaced by a TIP42 mounted on a heat radiator.

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10-minute timer 555 (CB9368E)
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1 W Amplifier (CB18192E)
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Frequency Divider With Unijunction Transistors (CB929E)
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