Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
Analog to Digital
Data Bus Circuits
Voltage to Pulse
Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
Voltage to Current
voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
DIY HV Variable Cap
DIY PMA alternator
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Speed Controler for R/C Models
Here`s how you can make an electronic speed controler (ESC) for your remote control car, boat or even an airplane using an old servo and some MOSFETS. Please note that this ESC has a very limited control range. Meanining that it will act almost like but better then a switch.
MOSFET H Bridge Schematic
No description available.
ELECTRONIC QUIZ TABLE
Here is a simple, low-cost quiz table for four game participants. It determines the contestant who first presses the switch (S1 through S4) to answer a question and locks out the remaining three entries. Simultaneously, the respective audio alarm sounds and the bulb glows. The quiz table can be used for more number of contestants simply...
Switched Mode Power Supply for LCD Monitor
This application note describes a complete flyback switched mode power supply that uses a Fairchild Power Switch. The MOSFET and its control IC are built into one package. The MOSFET is in fact a SenseFET. Various protection features are also included. Fairchild Power Switch can enhance the reliability and productivity of the system when...
simple switching power supply
I built a PCB for a simple switching power supply, originally designed by Keith Payea of the SRS. It uses an LM393, a P-channel power MOSFET, and darn little else. Since its frequency varies based on load (and nearly everything else imaginable), you can use junk-box parts and build it for cheap.
5 watt, 80 meter QRP CW Transceiver
1. Full 5 watt output using a power MOSFET final that is resistant to high SWR and thermal runaway. This final is very efficient and runs much cooler than traditional bipolar designs. 2. Highly sensitive and selective superhetrodyne receiver with plenty of audio to drive a speaker. About 100 Khz of tuning range is provided...
25 Watt MosFet Audio Amplifier
Can be directly connected to CD players, tuners and tape recorders. Simply add a 10K Log potentiometer (dual gang for stereo) and a switch to cope with the various sources you need. A correct grounding is very important to eliminate hum and ground loops. Connect in the same point the ground sides of R1, R4, R9, C3 to C8. Connect C11 at...
Cut Phone Line Detector
A while ago I got an email asking for the schematic of a circuit to detect cut phone lines. It didn`t take me long to find this circuit in Electronics Now. When the circuit detects that a phone line has been cut, it activates a MOSFET which can be used to drive a relay, motor, etc. It can also be connected to a security system.
MOSFET RGB LED PWM Driver
The RGB LED driver described on this page uses logic level 'N' channel MOSFETs which allow it to control LED arrays or lamps at up to 5 amps per channel without heatsinks. The driver uses exactly the same firmware as the small RGB LED driver shown in the photo so you can use the same code and sequences with this board to control big arrays...
Modern FM Converter
Here is my design for a modern receiving converter for pre-war FM sets. Accordingly, this article presents a design for listening to present day FM stations on a prewar FM set based on a MOSFET transistor and a TTL (transistor-transistor logic) packaged oscillator. Someone else might have done it with vacuum tubes, but this design suits me fine....
Since the volume control is after the gain stage, the preamp can be easily overloaded. I tried to limit the input signal by mounting a 470 k resistor in series with the CD input. A voltage divider is formed by this resistor and R107, resulting in a greater than 5-fold attenuation of signal input to the gain stage. Although the distortion had now...
Linear MOSFET voltage regulator
The circuit is a MOSFET based linear voltage regulator with a voltage drop of as low as 60 mV at 1 ampere. Drop of a fewer millivolts is possible with better MOSFETs having lower RDS(on) resistance. The circuit in Fig. 1 uses 15V-0-15V secondary from a step-down transformer and employs an n-channel MOSFET IRF 540 to get the regulated 12V output...
Optical switch detector with 555
When the phototransistor is stroken by IR light it conducts and the voltage between the 1Mohm resistor(arbitrary) and the phototrans drops from VCC to lower values. When the voltage drops lower than VCC/3 the 555 is triggered and goes high (from 0 TO VCC). The amount of light that strike the phototrans necessary to bring his collector to VCC/3...
Mosfet amplifier schematic 25 Watt
Can be directly connected to CD players, tuners and tape recorders. Simply add a 10K Log potentiometer (dual gang for stereo) and a switch to cope with the various sources you need. Q6 & Q7 must have a small U-shaped heatsink. Q8 & Q9 must be mounted on heatsink. Adjust R11 to set quiescent current at 100mA (best measured with an Avo-meter in...
Variable Fan Controller
When the fan seized up in my source and I changed it to a type with much less noise, turned on my computer, the largest source of noise CPU cooler fan. The computer I have a boxed Pentium III processor in slot 1, which is practically dismountable and fan replacement would be difficult. "Boxing" is a type of fan with ball bearings and replacement...
Touch switching 12V Light
The circuit on the right uses three bipolar transistors to accomplish the same result with the touch contact referenced to the negative or ground end of the supply. Since the base of a bipolar transistor draws current and the current gain is usually less than 200, three transistors are needed to raise the microamp current level through the touch...
Lamp Fader schematic
The sunset lamp comes on at full brightness and then slowly fades out over 1.5 hours time and stays off until power is recycled.
Automotive ignition coil
Here's a circuit to create a buzzcoil using a standard automotive ignition coil. A 556 dual timer is used to establish the frequency and duty cycle of the coil current. One of the timers is used as an oscillator to generate the 200 Hz rectangular waveform needed to control the (IRF740 MOSFET) while the second timer switches the oscillator on and...
Note Schematic Show Mosfet Gate Drive
Mosfet Audio Amplifier 20w Electronic Circuit Schematic Wiring
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Mosfet Circuits Simple Diagram Of Amplifier 30w Amp
Mosfet Power AmplifierCircuit Schematic Mosfet Power
Mosfet Power Amplifier Schematic Audio Circuit Circuitsfinder Free
Class-A MOSFET Amplifier by 2SK1058
I am using this Class A Amplifier with a 12AU7 based valve preamp. It produces the most purest sound. I have no idea of distortion levels etc. but it has a very fine grain and delicately textured quality. With only one watt of output efficient speakers must be used. Bass is better than the design predicts and the amp drives my 12 ³ 63L based 3-wa
Mosfet Amplifier OTL 100W by K1058J162
This includes a 220uF capacitor and two diodes to slow down the switch-on to reduce the output thump as the output capacitor charges through the speaker. This is not essential, depending on speaker sensitivity, with my own speakers there is just an unobtrusive low frequency sound at switch-on. With other applications such as a bi-amp or tri-amp sy
MOSFET IRF510 Capacitor Discharge Ignition(CDI) Circuit and explanation
A 2uF capacitor is charged to regarding 340 volts and also the discharge is controlled by an SCR. A Schmitt trigger oscillator (74C14) and MOSFET (IRF510) are used to drive the low voltage aspect of alittle (120/12 volt) power transformer and a voltage doubler arrangement is employed on the high voltage aspect to extend the capacitor voltage to re
Mini Amplifier using MOSFET
100W HiFi Power Amplifier with MOSFET
12W MOSFET Audio Amplifier 2SK135 / 2SJ50
Minimalist Mosfet Power Amplifiers
Single Ended Mosfet IRF510
555 Timer Circuits
RC Model Toy Circuits
H Bridge Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity