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FM Beacon Transmitter (88 108 MHz):  This circuit will transmit a continuous audio tone on the FM broadcast band (88-108 MHz) which could used for remote control or security purposes. Circuit draws about30 mA from a 6-9 volt battery and can be received to about100 yards.

FM Booster:  (Electronic circuit added 4/05)

FM Bug:  (Electronic circuit added 4/05)

FM Radio Telephone Bug:  (circuit added 7/02)

FM Radio Transmitter #1:  (circuit added 7/02)

FM Radio Transmitter:  (added 9/02)

FM Telephone Bug:  (Circuit added 9/04)

FM Transmitter #2:  (Electronic circuit added 4/05)

FM Transmitter 1KM Range (88-108 MHz):  1KM Range  (added 11/05)

FM Transmitter:  (Electronic circuit added 4/05)

FM Wireless Mike:  low power frequency modulated transmitter using two transistors. The circuit works with 9v power supply. . (Circuit added 9/04)

FPGA makes simple FIFO:  10/26/00  EDN-Design Ideas  / (added 2/06)  

Generate stabilized PWM signals:  08/17/00 EDN-Design Ideas  / (added 2/06)   

Green Current Mode PWM Controller FAN7601 / AN-4129:  Fairchild Application Notes / (app note added 6/06)

Grounding for Low-and-High-Frequency Circuits:  AN-345 - Analog Devices Application Notes  (app note added 6/06)Know Your Ground and Signal Paths for Effective Designs. Current Flow Seeks Path of Least Impedance-Not Just Resistance....

High Performance FM Receiver for Audio and Digital:  (Circuit / schematic design added 6/06)

High Power FM Bug:  (Electronic circuit added 7/03)

Improved FM Stereo Modulator:  (Electronic circuit added 7/03)

Improved frequency modulator uses negatron:  07/11/02 EDN Design Ideas  /  (added 1/05)  You can improve a capacitive-sensor circuit with a modulator and an RF transmitter (Reference 1) by modifying the modulator portion to obtain better accuracy. More improvements result from adding a "negatron" circuit, a configuration that uses equivalent negative capacitance. Reference 2 gives some insight into the uses of negative impedance....

KD2BD ATV AM Video Modulator:  video signal processing circuit that allows adjustment of video gain, video bias, sync and sync level (Electronic Schematic / circuit added 4/02)

Limiting Amplifier Forms AM Modulator:  12/07/95 EDN-Design Ideas / (Electronic Schematic / circuit added 4/02)  

LM2889 RF Modulator:  National Semiconductor - Application Note   (app note added 2/06)

Low Power FM Transmitter:  (added 9/02)