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555 timer help

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bubsta82

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I have found a simple 555 timer circuit; however, I need to change the button mechanism to something more suitable. It operates with an on-off push button switch but I am just wondering how pin 3 output could be turned on and off with a momentary switch instead of an on-off. only because i can only find a momentary switch small enough (tactile) to suit my needs. If there is a simple way or another switch that would help? All i need to do is turn off and on pin 3 output with the smallest switch possible.
http://i39.photobucket.com/albums/e151/bubsta82/555timercircuit.jpg
 
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Klemheist

New Member
555 momentary switching circuit

Bubsta,

Here's a 555 timer circuit that operates from a momentary switch.

The transistor in your schematic is replaced by a logic FET, which acts as a relay for whatever you want to switch on/off

In this one it is operating an LED Torch, however you can replace the LED by whatever you want to switch on and off
 

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bubsta82

New Member
I m just looking to see if there is a simple way to basically let a momentary be used to push once to shut the oscillation off and once pressed again start the oscillation again... and so on. and the higher the frequency the better this would work for me. Which i assume is by adjusting the values of the external Cap and resistors.
 

Boncuk

New Member
Use a JK-Flip-Flop to be connected to the pushbutton. Connect Q of the Flip-Flop to the reset pin of the timer via an NPN-transistor. When Q is high the timer stops oscillating keeping the output (pin3) low. When Q goes low the timer will run.

Boncuk
 

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bubsta82

New Member
hey just curious if this would help? After a lot of research i might have found a couple ways to achieve what I am looking for.

Circuits Page 9

What I am looking at is a little ways down titled
"Relay Toggle Circuit Using a 555 Timer"
 

bubsta82

New Member
hey just curious if this would help? After a lot of research i might have found a couple ways to achieve what I am looking for.

Circuits Page 9

What I am looking at is a little ways down titled
"Relay Toggle Circuit Using a 555 Timer"
 

bubsta82

New Member
hey just curious if this would help? After a lot of research i might have found a couple ways to achieve what I am looking for.

Circuits Page 9

What I am looking at is a little ways down titled
"Relay Toggle Circuit Using a 555 Timer"
 
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