Expander Compressor Unit Circuit | Compander

compressor expander unit

The compression and expansion are two important techniques used by audio engineers during recording and reproduction of program material. The compression of dynamic range of program material (records, speech or musical broadcasting) permits maintaining constantly high modulating level while the expansion, when used with the reproduction of compressed material, restores the dynamic range and creates a ‘live’ music. Thus, we are created simple and basic project Expander Compressor Unit Circuit. Circuit Description of Expander Compressor Unit Circuit | Compander Creating these effects is costly and complex, and beyond the scope of amateur…

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Hearing Aid Circuit

hearing aid circuit

The hearing aid circuit available in the market are fully transistorized and generally use a single pen cell. The hearing aid circuit uses an IC LM358 (IC1) for the same purpose which give better sensitive and performance. You can also check DIY Hearing Aid Circuit using 555. Circuit Description of Hearing Aid Circuit Operational amplifiers are used here in their simplest from non-inverting AC amplifier with a gain of 100. Op-amp A1 forms the first-stage amplifier. Second-stage amplification is given through op-amp A2. Hence the total gain is 10,000. Resistors…

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Guitar Amplifier | Convert Hawain Guitar to an Electric Guitar

guitar amplifier

Whereas an electric guitar with 60W PMPO (Peak Music Power Output) costs around $8, here is a cost effective solution to convert a Hawain guitar to an electric guitar. The circuit Guitar Amplifier | Convert Hawain Guitar to an Electric Guitar can also be used as an ampli-speaker with a tape recorder or a radio receiver. Circuit Description of Guitar Amplifier | Convert Hawain Guitar to an Electric Guitar The unit can easily be assembled on a standard TBA810 ampli-speaker PCB available in the market. It is also be housed in…

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Audio Running Lights Circuit

audio running light circuit

Here is a project for audio running lights circuit which uses filament bulbs instead of LEDs. The circuit employs seven channel darlington array IC ULN2004 and seven reversed biased zener diodes having different breakdown voltages. At low audio level, zener diodes having low breakdown voltages will conduct and corresponding lamps will light up. When output level increases, the other diodes will also conduct. As a result, you can see a very fine display of ‘moving’ light bulbs from top to bottom or from left to right, as per their arrangement.…

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100 Rung Exclusive Counter

100 rung exclusive counter

Digital counters are frequently needed in all kinds of counting circuits, test gear, sequential displays, timers, etc for up to ten outputs (exclusive and independent), or 16 at the most. But the problem arises when it comes to using more than these many outputs. In such a case, the 4017-based CMOS counter can be put to use as a 100-stage counter. The circuit configuration uses a dozen 4017 counter ICs. IC12 sends clock pulses to IC11 at one-tenth of its input frequency, which in turn allows Qa through Qj to…

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Electronics Fuse Circuit | Electronic Circuit Breaker

electronic fuse circuit

Fuse protection for electronics circuits seems to be an outmoded idea, for there are circuits (in computers etc) that consume high currents initially at a lower stable value. In case high-rated fuses are employed in such equipment to accommodate the initial surge current, it defeats the very purpose of protection. Slow-blow fuses often turn out to be too slow while quick-action fuses may blow out at the mere hint of a surge. An electronics fuse circuit of the kind described here provides an ideal solution in such cases. An electronic…

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Digital Clock Circuit with Seconds and Alarm Time Display

digital clock with second and alarm time display

Most of the digital clock available on the website is only capable to display hour and minute only. Now, here is a project called Digital Clock Circuit with Second and Alarm Time Display which shows not only ­hour, minute, and second but also alarm time. Best Engineering Projects (BEP) verify the project Digital Clock with Second and Alarm time display with the help of ten 7-segment displays and clock chip mm5387ANN. Circuit Description of Digital Clock Circuit with Seconds and Alarm Timer Display The entire circuit of the Digital Clock…

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Ultrasonic Lamp Brightness Controller Circuit

ultrasonic lamp brightness control receiver circuit

Wireless control of devices using infrared is not new to electronics hobbyists. Now, here is wireless control of the device using ultrasonic sound waves tested in BEP Lab. The project ultrasonic Lamp brightness controller circuit uses ultrasonic sound waves (above 20 kHz) for remote control of lamp brightness. Circuit Description of Ultrasonic Lamp Brightness Controller Circuit As with all wireless control systems, the Ultrasonic lamp-brightness controller comprises a transmitter and receiver circuit. Transmitter Circuit | Ultrasonic Lamp Brightness Controller Circuit The transmitter circuit generates an ultrasonic sound wave of about 40-50…

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Adjustable Bipolar Voltage Regulator Circuit Using LM337

adjustable bipolar voltage regular circuit

For op-amp circuits, the power supply must provide positive and negative voltages. Here is a simple circuit “Adjustable Bipolar Voltage Regulator” which gives a regulated ± 1.2V to ±2oV supply. ICs LM317K (IC1) and LM337K (IC2) are used here as positive and negative regulators respectively. Circuit Description of Adjustable Bipolar Voltage Regulator using LM337 The circuit diagram of the adjustable bipolar voltage regulator using LM337 is shown in figure 1, and is designed using two positive and negative adjustable voltage regulator IC, a step-down transformer, a bridge rectifier, and a…

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Hex to Binary Converter Circuit

hex to binary encoder circuit

The circuit described here is a hex to binary converter circuit using four, 8-input NAND gate 7430 ICs. The input keyboard switches SW1 to SW15 are connected in such a manner that the pressing of any switch produces the binary ABCD outputs of the corresponding decoded numbers. When all inputs in a NAND gate are high, it produces a low output, But when any of its input goes low, its output becomes high. Normally, all switches are open, the binary output is 0000. Pressing a switch gives a ‘low input’…

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