Water Level and TDS Sensor

This is a water level and TDS sensor circuit. Feature : Simple circuitry, Battery powered, 9V supply voltage, very low power consumption. Component : Resistor, capacitor, probe, battery, speaker, TLC555 timer IC, switch. [pbv.thunder-bay.on.ca]

Ultra-Sonic Ranging Circuit

This is an ultrasonic ranging circuit. Feature : The current consumption, at 2.5 Amps during the sonic burst, The 150mA quiescent current, The maximum range of 10.7 metre, The minimum range of 26cm. Component : Capacitor, resistor, PIC12C508, ST232CD, N1076, LM6032, LP301, transistor, diode. [robot-electronics.co.uk]

Ultrasonic Range & Imager Circuit

Description : The following circuit is ultrasonic range and imager circuit. Feature : one piezoelectric tranducer for tramsmit & receive, range of 2.5m, high gain. Component : crystal, resistor, capacitor, 1N4149 diode, 1N4148 diode, BC557 transistor, BC549 transistor, BF245, 4016, PIC12C509. [ele.uva.es]