Use this circuit instead of a standard on-off switch. Switching is very gentle. Connect unused input pins
to an appropriate logic level. Unused output pins *MUST* be left open!. First 'push' switches ON,
another 'push' switches OFF. You can use 1/4 watt resistors if they are metal-film type. Any proper
substitute will work for Q1, including the european TUN's. For C2, if you find the relay acts not fast
to an appropriate logic level. Unused output pins *MUST* be left open!. First 'push' switches ON,
another 'push' switches OFF. You can use 1/4 watt resistors if they are metal-film type. Any proper
substitute will work for Q1, including the european TUN's. For C2, if you find the relay acts not fast
enough, leave it out or change to a ceramic cap between 10 and 100nF.
Parts List
All resistors are 1/2 Watt and 5% tolerance.
R1 = 10K
R2 = 100K
R3 = 10K
C1 = 0.1µF, Ceramic
C2 = 1µF/16V, Electrolytic
D1= 1N4001
Q1 = 2N4401 (ECG123AP, NTE123AP, etc.)
IC1 = 4069, CMOS, Hex Inverter (14069), or equivalent
S1 = Momentary on-switch
All resistors are 1/2 Watt and 5% tolerance.
R1 = 10K
R2 = 100K
R3 = 10K
C1 = 0.1µF, Ceramic
C2 = 1µF/16V, Electrolytic
D1= 1N4001
Q1 = 2N4401 (ECG123AP, NTE123AP, etc.)
IC1 = 4069, CMOS, Hex Inverter (14069), or equivalent
S1 = Momentary on-switch
Copyright © Tony van Roon