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Help design a very simple momentary on/off circuit

Glhdata

Mar 18, 2017
5
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Mar 18, 2017
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Hello All;
I need help designing a simple circuit to turn on and off a load with a simple contact closure.
Supply is 6VDC (4-AA Batteries)
Want to turn on/off a 6VDC circuit that draws 70ma when on, from a contact momentary toggle.

Looked at using an NE555 but don't know how to calculate values or circuit design. Several are online, but don't know what values to use. I can put it together and have electronics knowledge that is basic.
I could also use a transistor switch because I can supply a 4VDC source but at a low current only, like a couple am only.
Any help appreciated.
George in Cali.
 

Arouse1973

Adam
Dec 18, 2013
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5,178
I am sure it will work at 6 Volts. Give it a try :)
Thanks
Adam
 

AnalogKid

Jun 10, 2015
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IF you don't want the size and expense of a relay

AND IF the circuit being controlled by the relay is using the same power source as the 555 circuit

THEN you can replace the two diodes and the relay with one resistor and one 2N4403 or 2N3906 transistor.

ak
 

KMoffett

Jan 21, 2009
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Those 555 circuits have to be powered all the time to do the ON/OFF operation. Is that OK for you circuit?

Ken
 

Glhdata

Mar 18, 2017
5
Joined
Mar 18, 2017
Messages
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Yes, I thought I would tra a transistor after I get the relay working. Great minds...



IF you don't want the size and expense of a relay

AND IF the circuit being controlled by the relay is using the same power source as the 555 circuit

THEN you can replace the two diodes and the relay with one resistor and one 2N4403 or 2N3906 transistor.

ak
 

Glhdata

Mar 18, 2017
5
Joined
Mar 18, 2017
Messages
5
That is exactly what I am doing. The circuit will get energized when the main unit is on, then I can turn the other device on and off with this.
Thanks to all who replied. I will update status when I get it built and working.
George


Those 555 circuits have to be powered all the time to do the ON/OFF operation. Is that OK for you circuit?

Ken
 
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