Tone Detector - This is also designed to be in conjunction with the sound detector amp/electret mike amp. this circuit is designed to trigger on a 1 khz tone. to change this frequencyrefer to the table below, then change the resistor and capacitor values accordingly __ Designed by Andy Wilson
Tone Generator - this tone generator can be used to control your robot. you will need to use the tone decoder for this. to widen the range, higher or lowersubstitute a higher, or lower valued capacitor for c1. __ Designed by Andy Wilson
Triple-Mode Tone Generator - Here is a simple circuit that generates three different tones. You can use it as a call bell, burglar alarm or any other security alarm.Fig.1 shows the circuit of the __ Electronics Projects for You
Tube provides linear tuning - 11/05/98 EDN-Design Ideas (File has many circuits, scroll to this one) Parallel LC circuits that you tune by changing capacitance have a nonlinear frequency-versus-voltage or frequency-versus-shaft-position characteristic. The frequency of an analog-tuned circuit is proportional to the reciprocal of the square root of the tuning capacitance. When you tune a bandwidth that is say, 5% or less of the center frequency, the frequency-versus-capacitance__ Circuit Design by Lyle Williams, Electronic Technical Services, New Orleans, LA
Two Tone Generator - This two-tone generator includes 3 ICs NE555 Astable Multivibrators. You can vary the duration of each tone by changing the 10k resistor or 100MF capacitor at IC1 or changing resistors and capacitors at IC1/2 for higher or lower tone. __ Designed by Andrew R. Morris
Two tone mixer IIP3 Notes - As a measuring experimenter with a homebrew POV, I like to add new test equipment and procedures to my lab each year. With digitally processed spectrum analyzers getting more able and relatively cheaper over time, I think a spectrum analyzer (with a built in tracking generator) might prove one of the best toys to consider buying. As ever, a homebrew SA remains a valid option for more advanced builders. __ Contact: Vasily Ivanenko
Two Transistor Amplifier - A 2 Watt audio amplifier made from discrete components. This was one of the earliest circuits that I ever designed and built, in Spring 1982. At that time I had only an analogue meter and a calculator to work with. Although not perfect, this amplifier does have a wide frequency response, low harmonic distortion about 3%, __ Designed by Andy Collinson
Two Watt Amplifier - An audio amplifier made from discrete components with 2 Watts audio power into an 8 ohm load. Carlos has used this amplifier on his AM radio for many years. __ Designed by Carlos Feldman
Voltage Controlled Panner - pans audio left and right __ Designed by G. Forrest Cook
Volume Control - This digital volume control has no pot to wear out and introduces almost no noise in the circuit. Instead, the volume is controlled by pressing UP and DOWN buttons. This simple circuit would be a great touch to any home audio project. __ Designed by Aaron Cake
Volume Control - A volume control using a linear pot that is much better than most log pots __ Designed by Rod Elliott ESP
Volume Control has Log Taper - 04/11/02 EDN-Design Ideas Digital potentiometers provide a compact and convenient way to attenuate audio-amplifier signals. However, most such potentiometers suffer from at least one flaw a nonlogarithmic step increment. To avoid this problem, a user must usually step the potentiometer in a nonlinear sequence to simulate a logarithmic taper__ Circuit Design by Doug Farrar, Los Altos, CA
Volume unit meter spans 60 DB dynamic range - 11/10/05 EDN-Design Ideas An audio volume-unit meter displays peak-related audio amplitudes to aid in accurately setting recording levels or for displaying an amplifier's operating conditions. A simple diode and capacitor network provIdeas a classic volume-unit meter's peak-weighted response, but the circuit typically limits response to about 23 dB of displayable dynamic range, and the meter suffers from errors that its pointer's inertia and mechanical "ballistics" introduce. Contemporary displays eliminate the inertia problem by using arrays of lighted elements to form bar graphs, but any shortcomings in response and accuracy characteristics now shift to the signal-processing domain. __ Circuit Design by Jon Munson, Linear Technology Corp, Sunnyvale, CA |