resister Ohms

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Well-Known Member
Jan 18, 2009
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I need to know how many Ohm res. Ill need for my Continuity tester and what type of buzzer I built a 8 pad launch controler its at 12vts
on what kind of igniters you're going to be using.
you want the current lower than what it takes to fire the igniter by a nice margin.
Limit the test current to 20 ma or less.

Using ohms law, R=V/I=12/.02=600 ohms for 20 ma, 1200 for 10 ma. Since these are not standard value, use the next highest values.

You can use a low current 85dB Piezo Buzzer from Radio Shack @ $4.29, Catalog #: 273-060.

Check out this thread for details.

Bob Krech