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Hobby Circuits designed by Dave Johnson

Last Updated on: Tuesday, June 01, 2021 03:22 PM


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Variable Gain Amplifier Circuits
Circuits designed by David Johnson, P.E. :

0VAC to 280VAC Variable Isolated AC Voltage

12v-24v AC & DC Day/Night Switch

AC to DC (240v to 5v)Power Supply

Capacitance-Based Touch Switch

Circuit Eliminates 9v Battery

LM317 adjustable voltage regulator used in Battery Eliminator Circuit

Touch Switch 240VAC

Voltage Boost

 

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Dave's Circuits

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