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Sweep Circuits
Last Updated on:
Wednesday, April 18, 2012 08:24 AM |
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| Circuits
Designed by Dave Johnson, P.E. : |
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3v Low Battery
Voltage Flasher
Many battery powered devices use two AA alkaline cells. Often you will not
know when it is time to replace the batteries until the device powered by them
actually stops operating. The hobby circuit below can be connected to a 3v
battery, to give you some warning when the battery is nearing its end of life.
It will flash a LED when the battery voltage drops to about 2.4 volts. The
electronic circuit draws only 1ua of current in standby mode and jumps to only 20ua
when flashing, so it can safely...
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Links to electronic circuits, electronic schematics, designs for engineers,
hobbyists, students & inventors:
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3V Sweeping Siren Alarm - The circuit uses a LTC1799 precision
frequency generator from Linear Technology. A 74HC14 hex Schmitt
trigger from Texas Instruments is also used to perform several other
functions. One section is wired as a simple 7Hz square wave
oscillator.… …. [Hobby Corner Circuit by Dave Johnson] |
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Timers Generate Variable Sweep Frequencies - 08/01/96 EDN-Design
Ideas.... EDN is migrating links. This link is not verified. Search
the "title" + "EDN" for new link. |
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| Sweep
Circuits |
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