Categories of electronic circuits

Audio amplifiers, preamplifiers, volume control and more...

Speed control, Car battery charger and other electronic devices for car

Games and entertainment
Electronic scoring game, the flashing heart, the millipede and more games

Card programmers, adapters and other circuits with microcontrollers

Schemstics that not included in other categories

Models and model remote control
Clap activated remote, infrared remote control, radio remote control and more...

Motor, light and power control
Dancing LEDs, Adjustable Strobe Light, Fading LEDs, Fancontrol...

Oscillators and timers
Amplifier Timer, Mini Metronome, Sawtooth wave generator, Simple IF Signal Generator...

PC related
PC based Frequency Meter, The Simplified I/O Interface, VGA to TV Scart...

Power Supplies, Ni -Cd Batteries Charger, Voltage Inverter and others..

RF circuit
FM and AM radio, FM Transmitter, Powerful AM transmitter and other RF circuits

12-way Input/Output Interface and others...

Security and other sensors and detectors
Fire Alarm, Metal Detector, Police Siren, UltraSonic Radar, Door Alarm...

Telephone related
Telephone amplifier, Smart Phone light, Conversation Recorder, Simple Phone Tap...

Test and measurement
Digital Voltmeter, Capacitance Meter, IR Remote Control Tester, Transistor Tester...

Video and TV
Elestronic devices for TV and video