Free Electronic Circuit Design
Low Power Requirement of Indication and The Solution Visual indication using light emitting diode becomes very common, because LED technology offer many benefits: low power consumption, durable, and cheap. Some indication must be able to draw strong attention, or at least it must be very clear to read whether its state is on of off. In some application, the requirement […]
Read more
To get various characteristic of an auto wah/quack effect, we need a flexible control of the envelope detection characteristic. Some playing styles need slow attack but fast decay, but some others don’t. Employing the envelope detector circuit presented in our previous article [Ref 1], but with some modification to make it single supply operation. Here we present the improvement of […]
Read more
Introduction to Envelope Detector Circuit Envelope detector circuit is used to get the amplitude profile of a signal. Some important properties of an envelope detector are attack or rise time and decay or release time. In the Figure 1, a signal is plotted in blue, and the detected envelope is plotted in black. Since it employs capacitor for filtering inside […]
Read more
Introduction to Automatic Wah/Quack Effect Automatic wah/quack effect gives a similar effect with the manual version (reference [1]), but without the need of any pedal to manually control the frequency/tonal sweep. This automation is made possible by detecting the envelope signal of the instruments audio signal, and use it to control the filter to produce center frequency sweep, producing audio […]
Read more
A type of guitar effect pedal that produce “wah”- or “quack”-like sound, which is similar to the crying sound of a baby is called wah-wah pedal, or just wah pedal. The effect is produced by filtering the musical instrument through a band-pass filter, which the center of its peak frequency is swept from low to high, mimicking audio tonal transition […]
Read more
Introduction: What is Fold-Back Distortion? I was introduced to a term of “fold-back distortion” in the past by an article from an old book which I forget what the title is, but the book contains schematic diagrams of many circuits collected from old publication of Elektor magazine (www.elektor.com). The article presents the circuit’s schematic diagram and how it works. I […]
Read more
Introduction While almost every audio equipments pay whatever it cost to minimize distortion, this kind of device does the opposite: distortion effect for electric guitar. Many methods have been implemented in producing a distorted signal from electric guitar pick-up, such as over-driven vacuum tube, solid-state (transistor), or diode clipper. The simplest form is passive diode clipper, which is implemented as […]
Read more
Similar with previous high voltage flip-flop circuit, this circuit controls high voltage (powerline) bulbs (220V AC). Instead of using transistors, this circuit uses NE555 integrated circuit, a very popular chip for timer or oscillator application. The required low voltage supply for 555 IC is provided by direct converter, made up by D1, R1, DZ1, and C1. This low voltage is […]
Read more
Using high (treble) and low (bass) frequency beat detection to control stage lamps can produce automatic light jockey for disco or any music performance. Instead of using general level of music signal to control a disco lamp, the circuit presented here uses two separate channel to give more complex variation of light flashing pattern. The dynamics of music signal is […]
Read more
A fluorescent lamp, also called a fluorescent tube is a tube with electrodes filled with low pressure mercury-vapor, utilizing fluorescence to generate visible light. The excitation caused by electric current in the gas of mercury vapor generate short-wave ultraviolet light. There is phosphor coating inside the tube an the ultraviolet light then make this coating glows. Conversion of electrical energy into […]
Read more
Using some active and passive components, we can build a simple audio-controlled disco light controller circuit. A standard audio power amplifier output, which usually drive loudspeaker, can used to drive this disco light circuit. With this circuit we don’t need light jockey anymore, because the flashing of the light will be directly controlled by the music signal itself. The schematic […]
Read more
With only few components, we can use resistors, diodes, and capacitor, we can convert line voltage (220VAC) directly to low DC voltage (10 VDC). This low voltage powers the low voltage flip-flop standard circuit, but this circuit is then used to drive high voltage SCR. This simple high voltage flip-flop circuit can be used to control alarm lamps, bell, or […]
Read more