Below circuit is the tone booster circuit. According to the name of circuit, the purpose is to amplify the sound signal to become more powerful in both low and high frequencies. There is no potensiometer used for bass/treble adjustment. Transistor type: Q1 – ztx384 ; Q2 – BC415p The circuit’s peaks frequencies is at 5000… Read More »
The circuit below is a Dynamic Mic Compressor circuit which is simple, easy to built, inexpensive but the results are quite satisfactory. Audio output sounded outstanding. The principle of this circuit is very simple, the first transistor is used as microphone pre-amplifier. Then a second transistor used as a buffer. And the third transistor is… Read More »
The following image is the scheme diagram of six LED stereo VU display circuit which build using Dot/Bar Display Driver IC LM3915. This VU display should be connected before amplifier module circuit. You may connect this circuit at pre-amp output, tone control input/output or equaliser input/output. This circuit powered with 12V DC supply. About LM3915:… Read More »
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 a stereo VU booster circuit diagram based on transistor FCS9014 which usually used for pre-amp and regulator circuit and switching. With simple circuit design, this device could be built easily. Scheme diagram, bottom PCB layout and component placement provided on the following image: This circuit should be connected to audio channel before amplifier… Read More »
Here is the AM Radio receiver circuit diagram based on old single IC MK484. Components List: R9, R10_________ 6R8 R6_____________ 100R R3_____________ 1K R1_____________ 4K7 R7_____________ 5K6 R4_____________ 10K R2_____________ 100K R5_____________ 150K R8_____________ 820K Pot_____________ 10K log pot Coil & ferrite bar set C7______________ 470p ceramic C, C4, C5, C6_____ 470nF monoblock C2______________ 100nF… Read More »
This circuit is a powerful three stage, 9V FM transmitter (Tx) with a range of up to 1 kilometer in the open. It uses an RF transistor in its output stage and two BC547″s for the first two stages. Distance of trans-mission is critically dependent on the operating Conditions (in a building or out on… Read More »
This a two station intercom. It uses two wires to run between each intercom unit. Each is self contained with its own battery, speaker, microphone and amplifier circuit. An LM386 audio power amplifier is used. It is widely available, used a minimum of external parts and is well suited to battery operation. It will give… Read More »
This is a low noise and distortion pre-amplifier and tone control circuit in one module. Using a special IC TDA1524A, this simple circuit is easy to build and will drive most of power amplifier. Schematic diagram: