200 Watt power audio amplifier



Output Power : 200Watts
Load Resistance : 8ohms
Input impedance : 55K
Maximum supply voltage : (+95v)-0-(-95v)
Recommended supply voltage : (+66v)-0-(-66v)

This complete high quality, low noise mono audio power amplifier is based around the Hybrid Integrated Circuit STK4050 manufactured by Sanyo.
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FM Transmitter 4Watt


stabilized tendency of catering: Vcc=12~16V
Frequency of emission: 88~108MHz
Consumption: 100~400mA

Circuit diagram:

The resistors are 1/4W.
R1, R2 10KOhm
R3 47Ohm
C1, C2 1nF
C3 4,7uF/16V
C4, C7, C8 0~45pF trimmer
C5, C6 10pF
C9 100nF
L1 4 turns, 7mm diameter *
L3 3 turns, 7mm diameter *
L4 5 turns, 7mm diameter *
L2 RF choke VK200
T1,  2N2219

T2, 2Ν4427 or MRF 237
ANT Simple dipole l/2.
MIC IN Microphone dynamic or other type. (It can also connected to a cassette player unit)

* The inductors is air from wire of coaxial 75W or other 1mm roughly.
Before you print it out with microsoft paints, set the screen resolution to 1280 by 1024 in order to get the correct scale

FM Transmitter 4Watt pcb


FM Transmitter 4Watt parts

Components Layout

With the C4 we regulate the frequency.
With their C7, C8 we adapt the resistance of aerial (practically to them we regulate so that it is heard our voice in the radio as long as you become cleaner).
The T2 wants refrigerator.


HI-FI Stereo Multiplexer for FM transmitter with NJM2035 I.C. circuit
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Radio only 1 transistor without electricity

Experts and amateurs have been Experimenting with radios without batteries since the wireless communication started.
In many designs we've seen radios that operate without power, but all are known to use the diode 1N34. (Crystal Radio).
Although significant improvements have increased the sensitivity and selectivity of these system circuits, Performances were limited until new techniques have emerged.
Am radio diagram
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100W Audio Power Amplifier

General Description

This is an exceptionally well designed amplifier, with a lot of power reserve, high fidelity, low distortion, good S/N ratio, high sensitivity, low consumption and full protection. Having all these almost ideal characteristics this amplifier is likely to become the basic building block of your future high fidelity system, or it can also become the element that will upgrade your existing system.
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1Volt Low Power Stereo Headphone Amplifier with Shutdown MAX9725

Low-Power, Stereo Headphone Amplifier with Shutdown
The MAX9725A–MAX9725D fixed-gain, stereo headphone amplifiers are ideal for portable equipment where board space is at a premium. The MAX9725E offers the flexibility to adjust the gain with external input and feedback resistors.
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Power Amplifier 250 - 500 Watt with transistors MJ15003

Amplifier 250 - 500W

Amplifier 250 - 500W circuit
GENERAL DISCRIPTION: The circuit is based around (TL 071) manufactured by NATIONAL semiconductors (MJ15003) by ON semiconductors It is a high fidelity audio power amplifier.
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BH1415F FM Stereo Transmitter

This Electronic circuit is a stereo FM Transmitter based on BH1415F wireless audio link IC. Phase Locked Loop (PLL) controller use PIC16F628 and the the PLL frequency programming can be displayed with 8x2 and 16x2 LCD. Frequency Range 88-108 MHz
FM Stereo Transmitter ( BH1415F )

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240 Volt AC TO 5 Volt DC Power supply

This is simple way to power some 5 volt logic from a 240vac source. If a 120 volt ac power adapter is used, the circuit will also work for 120 volt ac power lines.


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This circuit has 3 main sections, an inverting op-amp amplifier, a rectifier and LED display. The input can be from almost any low level source, but if not using an electret microphone, then omit R1 as it's not necessary.
The gain of the amplifier based around IC1 is controlled by VR1. The output is rectified by D1,2 and filtered using C4,R6.
The final stage is a standard design for the LM3914. Alter R8 to control LED brightness but be careful not to over-drive the IC's. It's recommended that you don't
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TDA1562Q 50 Watt from a 12 V battery

TDA1562Q  50W from a 12 V battery

The integrated output amplifier described in this article consists of little more than one integrated circuit. It is intended especially for use in motor vehicles and other batteryoperated applications.
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LM3876 - High-Performance 56W Audio Power Amplifier with Mute

High-Performance 56W Audio Power Amplifier

The LM3876 is a high-performance audio power amplifier capable of delivering 56W of continuous average power to an 8 load with 0.1% THD+N from 20Hz-20kHz.
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LM1875 Power audio amplifier 20 Watt



The LM1875 is a monolithic power amplifier offering very low distortion and high quality performance for consumer audio applications.
The LM1875 delivers 20 watts into a 4Ω or 8Ω load on ±25V supplies. Using an 8 load and ±30V supplies, over 30 watts of power may be delivered.
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2.5 GHz Frequency Counter with Blue 2x16 LCD display

2.5 GHz Frequency Counter with Blue 2x16 LCD display
This project explain a very powerful frequency counter which has many useful software functions.
The software can add or subtract 3 different IF frequencies (±455 kHz ,±10.7 MHz and ±21.4 MHz).

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FM Transmitter 2 Watt


The circuit is basically a radio frequency (RF) oscillator that operates around 100 MHz. Audio picked up and amplified by the electret microphone is fed into the audio amplifier stage built around the first transistor. Output from the collector is fed into the base of the second transistor where it modulates the resonant frequency of the tank circuit (L1 coil and the trimcap) by varying the junction capacitance of the transistor. Junction capacitance is a function of the potential difference applied to the base of the transistor T2. The tank circuit is connected in a Hartley oscillator circuit.
FM Transmitter 2 Watt
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10.5 Watt Push-Pull audio tube power amplifier 6H9C - 6P13С


The output stage: push-pull, class A, with a fixed offset in 6P13S tubes in triode switch.Output Power - 10.5 WBand Frequency - 25Hz ... 30kHzSensitivity - 0.707V (1V amplitude)THD - 1.5% (before clipping), 0.8 ... 0.9% (half power)The level of background noise on the output - 1.5 mV

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12 Volt Tube Distortion for guitar

IC1---LM747 dual op-amp, others may be substitued but pinout will differ
IC2---LM340K 12 Voltage Regulator
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30 Watt audio power amplifier for cars

Design by T. Giesberts



The power that can be obtained from a standard car radio amplifier operating from a 12 V car battery is 5–6W, which (for many listeners) is not really enough for satisfactory hi-fi reproduction.
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Power Amplifier 1500W - 4OHMS

Power Amplifier 1500W - 4OHMS
This project is mainly in answer to those for whom no amount of power is enough. I have lost count of the number of times people have asked if it's alright to increase the supply voltage on every circuit published, and in general the answer is no - it's not alright. Every design on this site is optimised for the stated power. There is always some flexibility, but you must be very careful to make sure that transistor safe operating area (SOA) is not exceeded. There is also a maximum voltage for any semiconductor, and devices must be selected to ensure they are used within their ratings. MORE...

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One tube broadcaster

The purpose of this broadcaster is to transmit your favorite music to every AM radio in your home. The transmitting power is so low that it should not bother the neighbors. A common application would be to drive it from the speaker leads of your FM radio, which could then include playing your XM or Sirius to your AM sets, or just your favorite FM station.


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