This is Vice Control Music Outlet circuit using SL517A, this electronic circuit project build a very easy. The circuit is shown in Figure, and it is composed of acoustic sensor, voice control IC, relay control circuit, song voice circuit and AC buck rectifier circuit.

Vice Control Music Outlet Circuit using SL517A:





Voice control IC uses SL517A which contains high-gain amplifier, bistable flip-flop and buffer output level, and it has two packages of dual in-line and black ointment. Its internal functional block diagram is shown as below.

2x300W or 600W Power audio Amplifier Circuit Diagram:




The circuit includes thermal shutdown circuitry that activates when the die temperature exceeds 150°c. CIRCUIT’s mute function, when activated, mutes the input drive signal and forces the amplifier output to a quiescent state. Maximum Output power @ 8ohms : 300watt. Absolute max power supply voltage :±38V to ±40V. Recommended power supply voltage :±30V to ±35V.

It is a very simple build a simple Audio-oscillator Circuit Diagram  Project. The circuit`s frequency of oscillation is/= 2.8/ [C1 x (R1 + R2)]. Using the values shown, the output frequency can be varied from 60 Hz to 20 kHz by rotating potentiometer R2. A portion of IC1`s output voltage is fed to its noninverting input at pin 3.

Audio Oscillator Circuit Diagram:



The voltage serves as a reference for capacitor Cl, which is connected to the noninverting input at pin 2 of the IC. That capacitor continually charges and discharges around the reference voltage, and the result is a squarewave output. Capacitor C2 decouples the output. 

Here is a very simple and easy to use audio amplifier using I.C BEL(Bharat electronics limited)1895 , a very common IC. This circuit can run on 3V to 6v , making it easy to use in pocket amplifier. Cost is under 25/-

Sooper Amplifier Using BEL1895 I.C:



 
Parts list:

BEL1895 I.C (DIP8),
C1 = 470uF/10V,
C2 = 1000uF/16V,
C3 = 220uF/10V,
C4 = 100uF/10V,
C5 = 4.7uF/10V,
C6 = 47pF,
C7,C8 = 1uF,
R1 = 47Ohm,
R2 = 470Ohm,
R3 = 100K,
R4 = 1Ohm,
R5 = 10K V/C,
speaker, etc…
Total cost is around 20-30 rupeess(INR) or 0.6USD.

Whenever I'm in the car listening to my favourite CD, it always happens; my batteries go dead. To solve that problem, I built this extremely simple regulator circuit. It steps down the 12V from the lighter socket to 9V which is used by the CD player. Different CD players (I have a Sony Discman) may require different voltages, so just use the correct regulator. All the 78xx series regulators have the same pin out, so the circuit is universal.

Portable CD Player Adapter For Car Circuit diagram:




Parts List

• The voltage your CD player needs will determine which regulator you use. For 9V, use the 7809. For 6V, use the 7806. For the unlikely 5V use the 7805. Remember that whatever regulator you use, you will need to heat sink it. The metal case or metal cover on the case makes a great heat sink.
• I built the circuit in a small case with the long wire to the cigarette lighter plug coming out one end, then another, slightly shorter wire going out the other end to the CD player.

• Triple check your wiring. You would hate to ruin an expensive CD player because you reversed one of the connections or hooked the regulator up backwards.

This tremolo effect circuit uses the XR2206 and the TCA730 IC which is designed as an electronic balance and volume regulator with frequency correction. The circuit is use full for stereo channels and it also has the ability to simulate the Lesley effect aka rotating loudspeaker effect.

How does the Tremolo Effect Circuit works:
Balance and volume settings are done with a linear potentiometer for both channels. If this potentiometer is replaced with an AC voltage source, a periodic modulation of the input signal can be achieved. This AC voltage source comes from the function generator IC XR2206. This IC generates square, triangle and sine wave signals but for this project we use only the sine wave.

IC Tremolo Effect Circuit diagram:


The modulation voltage can be varied with P1 from 1 Hz up to 25 Hz. Resistor R3 sets the operation level of the sine wave generator. R5 and R6 set the DC voltage and the sine wave amplitude at the output. C2 is a ripple filter. The square wave output of the XR2206 drives T2 and a LED to optically display the frequency.

The modulating voltage reaches pin 13 of TCA730 via P3 and R10. This input functions as the volume control or in this case the volume modulation. The degree of the balance modulation (Lesley effect) can be varied with P2. A regulated power supply using 7815 IC is recommended. Do not use a non-stabilized power supply since the current variations would influence the modulation negatively.