The following diagram is the circuit diagram of 20 band stereo graphic equaliser which will controlling the audio signal in specific frequency range. The power supply used for this circuit is symmetrical (dual polarity) type, 15V DC.
This is the circuit diagram of a voice operated relay. It similar with sound activation switch circuit which will turn on and turn off (connect and disconnect) the switch depending on the sound input. The output switch of this circuit is act by a relay. Components list: R1, R7 : 1K R2, R4, R8 :… Read More »
This is a very simple FM receiver which build based on one transistor only. No chip or another active component. The output is connected to earphones, you need an amplifier circuit if you want to listen the radio with a loudspeaker.
This is 0-24VDC digital PIC power supply circuit. This variable power supply controlled with PIC microcontroller. There is LCD display in this circuit which will show the actual value of power supply output. This power supply use push on switch to adjust the output voltage and current value. Schematic Diagram: Component List: C1 = 2000uF… Read More »
This is a class AB 6-10W audio power amplifier circuit which built using a TDA2002 or TDA2003 power amplifier IC module. These are replacements for the original LM383 which is no longer available. It is easy to build and has a minimum of external components. The module has both short circuit protection and thermal protection.… Read More »
Here is the wailing alarm siren circuit diagram: Components List: R1,R5___________ 4.7K R2______________ 47K R3______________ 10K R4______________ 100K Rx______________ *see text C1,C4__________ 100uF/25V, electrolytic C2,C3__________ 0.01uF (10nF), ceramic T1_____________ 2N3702 (NTE159, TUP, etc.) IC1,IC2________ LM/NE555, MC1455P, etc LS_____________ Loudspeaker
The following diagram is the circuit diagram of basic monostable multivibrator based IC timer 555. This circuit uses only 4 electronic components that are a timer IC, two capacitors and a resistor. Components List: A multivibrator is an electronic circuit used to implement a variety of simple two-state systems such as light emitting diodes, timers… Read More »
Above schematic diagram is a small 325mW amplifier circuit based on LM386 with a voltage gain of 200 that can be used as a simple bench amplifier, signal tracer or used to amplify the output from personal radios, MP3 players, MP4 Players or iPods.
This is the circuit of LED color fade effect. Just like the name of the circuit, the light intensity of LEDs in this circuit will fade from high intensity to low intensity and then off. Here the final result preview: