Found in Texas Instruments documentation from the 90's, this circuit can be used as a shield due its symmetrical power is 5 V. The circuit has offset adjustment and a pass band of 200 kHz.
This circuit consists of a traditional version amplifier with complementary output transistors...
The tones of this circuit are determined by the feedback resistors on the oscillators with the...
The circuit shown is from the National Semiconductor FET manual. Field effect transistors and...