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Circuits designed by David Johnson, P.E.
Last Updated on: Wednesday, October 18, 2017 05:04 AM

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More  Active Filters: Low Pass

3KHz LOW PASS FILTER PLUS AUDIO AMP
 

This circuit uses a switched capacitor filter IC from National Semiconductor to filter signals with frequencies higher than the 3KHz needed for voice audio. The schematic includes an audio Amplifier that is designed to drive a standard audio head phone. The circuit is described in more detail in the receiver section of Dave Johnson's Handbook of Optical Through the Air Communications. (this link is off-site)

Click on Drawing Below to view PDF version of Schematic

Circuit 3KHz Low Pass Filter & Audio Amp designed by Dave Johnson, P.E. (June 4, 2000)

 

More  Active Filters: Low Pass

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