Touch-sensitive switch

Posted on Jul 21, 2012

A high impedance input is provided by Ql, a general purpose field effect transistor

Touch-sensitive switch
Click here to download the full size of the above Circuit.

741 op amp is used as a sensitive voltage level switch which in turn operates the current Q2, a medium current PNP bipolar transistor, thereby energizing the relay which can be used to control equipment, alarms, etc.

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Viswanathan R Elayidom   May 6, 2020

Would like to have a vhf/uhf dual band linear amplifier circuit with output of not less than 50watts.

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