interupting a circuit

[KTW]

What device could I use operate a 9 volt buzzer and then quit or possibly reactivate after 3-5 seconds?

 

[BobK]

A monostable multivibrator.

Bob

 

[KTW]

Thank you Bob, I'm looking at the 555 timer IC.
I've never used one but they're cheap enough to try.

 

[Harald Kapp]

Dependig on your timing requirements (how long do you want the buzzer to be active, how long is the pause in between, how often do you want the buzzer to sound) you may want to look into a small microcontroller to control the timing by a few lines of software.

 

[KTW]

Hi Harald ;
This would be for a garage intrusion alarm activated by a PIR so I would want it to operate intermittently until the PIR stopped sensing which is about 10 to fifteen seconds.
I just don't want a constant buzz.

 

[Harald Kapp]

Then a 555 in astable multivibrator mode will be fien, no need for a microcontroller.

 

[KTW]

Thanks for the assistance, there's lot's of information on YouTube with regard to the 555, should be fun putting it together.

Kevin.

 

[CDRIVE]

Hi Harald ;
This would be for a garage intrusion alarm activated by a PIR so I would want it to operate intermittently until the PIR stopped sensing which is about 10 to fifteen seconds.
I just don't want a constant buzz.

Keep in mind that you can purchase a inexpensive Sonalert which is a Piezo element driven by an integral oscillator. There are 3 wire models available that can be operated as a constant tone or intermittent beeps (~1BPS) by simply applying power to the intermittent conductor and (-) common.

Chris

 

[KTW]

Thanks Chris, I wasn't aware of that.
I'll have a look at them also.

 

[CDRIVE]

You're welcome. I used to get them at Radio Shack because they were convenient,... back when they used to stock components.

Chris