Electronic Schematics
FM Transmitters
PLL Synthesizers
Stereo Encoders & Decoders
Antennas
FM Receivers
Audio / Amplifiers
Power Supplies
AC/DC Inverters AC/DC Converters
Battery Chargers
Remote Control
PC Related
Test & Measurement
PIC / ATMEL / AVR
USB Circuits
Telephone Related
LED
Miscellaneous Circuits
Stepper Motors

 Schematics  >> 

Page 5 of 9:   1   2   3   4   5   6   7   8   9
Lightning Detector
This DIY lightning detector circuit is a very sensitive static electricity detector that can provide an early warning of approaching storms from inter-cloud discharge well before an earth-to-sky return strike takes place. An aerial (antenna) formed of a short length of wire detects storms within a two mile radius. The circuit emits an audible warning tone from a piezo buzzer, or flashes an LED for each discharge detected, giving you advance warning of impendig storms so that precautions may be observed.


LM386 Audio Probe Amplifier
LM386 audio probe amplifier is an essential tool for troubleshooting audio stages in audio related circuits such as amplifiers, oscillators, function generators, phone circuits, radios and lots of our other projects. It is a very handy piece of test equipment that can be built on pre-drilled board and will make a perfect addition to your electronic collection. There are lots of things that can go wrong with an audio stage. It can produce distortion or a “hollow” sound, go weak or simply fail altogether. Likewise tone circuits can present a number of faults and it is very handy to be able to “hear” what is going wrong. It is not sufficient to measure the DC voltages on these stages. This only gives a partial picture of the conditions and does not tell you the quality of the audio being processed. To determine this you need a piece of test equipment that will let you see or hear what is being processed. Some of the projects you can test with the Mini Bench Amplifier are tone circuits while others are audio circuits. Tone circuits and audio stages are surprisingly difficult to test unless you have an audio probe or a oscilloscope. Oscilloscope is an ideal piece of equipment but if your budget does not extend this far, the next best thing is an audio probe.


Microphone Amplifier with TDA7050 IC
Here's a simple microphone amplifier based around TDA7050 IC. There are many schematics, the choice fell on the amplifier chip TDA7050, the only downside was it that it was not appointed to the microphone. By adding a resistor R1 in the scheme by 4,7 kOhm - amplifier can no longer work with conventional condenser microphones. If you remove the resistor R3 - the alarm will be put on a small speaker with an impedance of winding 32 Om'a. Voltage amplifier is powered by 3 - 5 volts, but as the amplifier must be nourished from 12 in the scheme of linear stabilizer was added at 5 V. This scheme was checked with headphones (current consumption was 50 mA) and connect to the line input of your TV.


Mini Metronome
Linear scale - Small size 40 to 208 beats per minute


Motion Activated Camera
I made a relatively simple attachment to my Canon SLR to create a motion activated camera using Arduino. A lot of this was based on and inspired by the intervalometer project at The Honey Jar. I made some changes to his circuit to use a 4N35 optocoupler instead of reed relays.


One Button Digital On-Off Switch
The load is driven by the MOSFET IRFZ44 and 4093 AND gates are used in the circuit. The output of the 4093 IC drives the MOSFET. Only one button allows you to change the on-off state of the electronic circuits in which you use this switch. The circuit schematics is above. Click image to see the larger schematics diagram.


Oscilloscope Probe Schematic & Anatomy
Passive Probe are the most general used scope probe. As the name "passive" suggest, it is made from passive components resistor, capacitor & wires. The leading scope probe maker are LeCroy, Tektronix & Agilent. Passive probe usually comes with attenuation factor of 1:1, 10:1 and 100:1. Attenuation factor of 1:1 means whatever signal being probe at the probe tip will be shown exactly as it is at the oscilloscope input. So a signal of 1V at the probe tip will be detected as 1V at the scope input. Attenuation factor of 10:1 means that a signal of 1V at probe tip will be detected as 0.1V at the scope input.


PAL/NTSC Video Text Generator
Perfect low cost solution for: * New video security installations * SSTV transmitters * Amateur video * Existing installed security installations * Scientific experimentation monitoring * and any other application that needs the time and date recorded on an image!


Park Assist Circuit
Park Assist circuit was designed as an aid in parking the car near the garage wall when backing up. LED D7 illuminates when bumper-wall distance is about 20 cm., D7+D6 illuminate at about 10 cm. and D7+D6+D5 at about 6 cm. In this manner you are alerted when approaching too close to the wall. All distances mentioned before can vary, depending on infra-red transmitting and receiving LEDs used and are mostly affected by the color of the reflecting surface. Black surfaces lower greatly the device sensitivity. Obviously, you can use this circuit in other applications like liquids level detection, proximity devices etc.


Parrot Sounding AC door Bell
Here is a mains-operated doorbell that produces parrot-like sweet voice without requiring any musical IC. The circuit is cheap and easy to construct. The AC mains is fed to the circuit without using any step-down transformer.


Page 5 of 9:   1   2   3   4   5   6   7   8   9


Accurate LC Meter Capacitance Inductance Meter with 16F628 and LCD
Volt Ampere Meter with 16F876 Microcontroller and LCD display
 
Accurate LC Meter

Build your own Accurate LC Meter (Capacitance Inductance Meter) and start making your own coils and inductors. This LC Meter allows to measure incredibly small inductances making it perfect tool for making all types of RF coils and inductors. LC Meter can measure inductances starting from 10nH - 1000nH, 1uH - 1000uH, 1mH - 100mH and capacitances from 0.1pF up to 900nF. The circuit includes an auto ranging as well as reset switch and produces very accurate and stable readings.
PIC Volt Ampere Meter

Volt Ampere Meter measures voltage of 0-70V or 0-500V with 100mV resolution and current consumption 0-10A or more with 10mA resolution. The meter is a perfect addition to any power supply, battery chargers and other electronic projects where voltage and current must be monitored. The meter uses PIC16F876A microcontroller with 16x2 backlighted LCD.

50MHz 60MHz Frequency Meter / Counter with 16F628 & LCD
1Hz - 2MHz XR2206 Function Generator
60MHz Frequency Meter / Counter

Frequency Meter / Counter measures frequency from 10Hz to 60MHz with 10Hz resolution. It is a very useful bench test equipment for testing and finding out the frequency of various devices with unknown frequency such as oscillators, radio receivers, transmitters, function generators, crystals, etc.
1Hz - 2MHz XR2206 Function Generator

1Hz - 2MHz XR2206 Function Generator produces high quality sine, square and triangle waveforms of high-stability and accuracy. The output waveforms can be both amplitude and frequency modulated. Output of 1Hz - 2MHz XR2206 Function Generator can be connected directly to 60MHz Counter for setting precise frequency output.

BA1404 HI-FI Stereo FM Transmitter
USB IO Board PIC18F2455 / PIC18F2550
BA1404 HI-FI Stereo FM Transmitter

Be "On Air" with your own radio station! BA1404 HI-FI Stereo FM Transmitter broadcasts high quality stereo signal in 88MHz - 108MHz FM band. It can be connected to any type of stereo audio source such as iPod, Computer, Laptop, CD Player, Walkman, Television, Satellite Receiver, Tape Deck or other stereo system to transmit stereo sound with excellent clarity throughout your home, office, yard or camp ground.
USB IO Board

USB IO Board is a tiny spectacular little development board / parallel port replacement featuring PIC18F2455/PIC18F2550 microcontroller. USB IO Board is compatible with Windows / Mac OSX / Linux computers. When attached to Windows IO board will show up as RS232 COM port. You can control 16 individual microcontroller I/O pins by sending simple serial commands. USB IO Board is self-powered by USB port and can provide up to 500mA for electronic projects. USB IO Board is breadboard compatible.

RF Remote Control 433MHz Four Channel
100m 4-Channel 433MHz Wireless RF Remote Control
 
200m 4-Channel 433MHz Wireless RF Remote Control

Having the ability to control various appliances inside or outside of your house wirelessly is a huge convenience, and can make your life much easier and fun. RF remote control provides long range of up to 200m / 650ft and can find many uses for controlling different devices, and it works even through the walls. You can control lights, fans, AC system, computer, printer, amplifier, robots, garage door, security systems, motor-driven curtains, motorized window blinds, door locks, sprinklers, motorized projection screens and anything else you can think of.
100m 4-Channel 433MHz Wireless RF Remote Control

Four button RF remote is used to turn ON / OFF four different devices independently. Any of the four outputs can be configured to work independently in either toggle or momentary mode. Outputs are buffered by BC549 NPN transistors and can drive low voltage devices directly or be connected to either 5V or 12V relays (or motors) to control appliances that use 110V / 220V mains voltage or any voltage of your choice. Multiple remote systems can be used independently to control more than four appliances in the same location by changing the address code on 433MHz receiver and remote. It is also possible to use several remotes to control the same appliance such as garage door.
 
 Latest Schematics
Curious C-Beeper
Automatic Night Light
LM386 Utility Amplifier
Mini FM Transmitter
Automatic Garden Light
USB Battery Pack
Phone Transmitter
27MHz Walkie Talkie
Plant Water Alarm
4km FM Transmitter
1 Watt FM Transmitter Amplifier
Simple MOSFET Switch
AM Radio Transmitter Using 555 Chip
Adjustable Bench Power Supply
Arduino RF link using 433MHz Transmitter / Receiver modules
MAX038 Generator
Adjustable Constant Current Load
68W LM3886 Amplifier
18W FM Transmitter
Solar Charger for USB Devices
500W Modified Sine Wave Inverter
3.3V and 5V Power Supply
Veronica 1W FM Transmitter
Transformerless Joule Thief
1W PLL Transmitter with MC145152
Eliminating LED Christmas Lights Flicker
100m Simple FM Transmitter
PCM5102 Burr-Brown DAC with DIR9001 SPDIF Receiver
Simple FM Transmitter with BC549
Simple MP3 FM Transmitter

Electronics-DIY.com © 2002-2014. All Rights Reserved.