This circuit is of an 2x 2,500W RMS stereo amplifier, super-light and without switching-mode power supply. The circuit just shows a channel, and the power supply that it assists to the two channels. The audio circuit should be duplicated, but the power supply assists to the two channels without problems. A special care should be [...]
The circuit of AM transmitter is designed to transmit (amplitude modulated) DSB (double side band) signals. A modulated AM signal consists of a carrier and two symetrically spaced side bands. The two side bands have the same amplitude and carry the same information. In fact, the carrier itself coveys or carries no information. In a [...]
Micro Power AM Broadcast Transmitter In this circuit, a 74HC14 hex Schmitt trigger inverter is used as a square wave oscillator to drive a small signal transistor in a class C amplifier configuration. The oscillator frequency can be either fixed by a crystal or made adjustable (VFO) with a capacitor/resistor combination. A 100pF capacitor is [...]
This circuit consists of two identical intercom units. Each unit contains a power supply, microphone preamplifier, audio amplifier and a Push To Talk (PTT) relay circuit. Only 2 wires are required to connect the units together. Due to the low output impedance of the mic preamp, screened cable is not necessary and ordinary 2 core [...]
Mixer circuit above has 3 line inputs and 3 mic inputs. The mic inputs are suitable for low impedance 200-1000R dynamic microphones. An ECM or condenser mic can also be used, but must have bias applied via a series resistor. As with any mixer circuit, a slight loss is always introduced. The final summing amplifier [...]
18w Audio Amplifier with Power Supply Amplifier parts: P1_____________22K Log. Potentiometer (Dual-gang for stereo) R1______________1K 1/4W Resistor R2______________4K7 1/4W Resistor R3____________100R 1/4W Resistor R4______________4K7 1/4W Resistor R5_____________82K 1/4W Resistor R6_____________10R 1/2W Resistor R7_______________R22 4W Resistor (wirewound) R8______________1K 1/2W Trimmer Cermet (optional) C1____________470nF 63V Polyester Capacitor C2,C5_________100µF 3V Tantalum bead Capacitors C3,C4_________470µF 25V Electrolytic Capacitors C6____________100nF [...]
Mosfet 25W Audio Amplifier Part List: R1,R4_________47K 1/4W Resistors R2____________4K7 1/4W Resistor R3____________1K5 1/4W Resistor R5__________390R 1/4W Resistor R6__________470R 1/4W Resistor R7___________33K 1/4W Resistor R8__________150K 1/4W Resistor R9___________15K 1/4W Resistor R10__________27R 1/4W Resistor R11_________500R 1/2W Trimmer Cermet R12,R13,R16__10R 1/4W Resistors R14,R15_____220R 1/4W Resistors R17___________8R2 2W Resistor R18____________R22 4W Resistor (wirewound) C1___________470nF 63V Polyester Capacitor C2___________330pF [...]
