Free Simple Circuit Diagram
A signal conditioner for pH meter probe is required to have high input impedance. The signal conditioning of the pH meter probe is done by providing a buffer with gain, offset, and volatge to frequency converter. High input impedance requirement for pH probe while maintaining low cost constraint is given by 3130 CMOS opamp. Output of probe, is amplified by […]
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Most cases of infra-red remote control failure can be detected by detecting the absence of the pulsed transmitted infra red light. It’s very rare that the remote control fail while it is still capable of transmitting the infrared pulse. This condition enable such a very simple tester is easy to build. A simple infrared detector with ac coupling and simple […]
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An oscillator can be built using LC (inductor-capacitor) tank circuit. When we vary the capacity of the capacitor in LC tank circuit then the frequency of the oscillator will vary according to capacitance change. The idea of this modulator is by employing a varactor (voltage-dependent variable capacitor) in the LC tank circuitry. As the capacitance is controlled by a voltage […]
Read moreA pH meter circuit is basically an amplifier to boost a voltage signal which is produced by a pH probe. The pH probe itself is equal to a battery cell when submersed in the measured solution, producing a weak voltage and current signal. High input impedance requirement for pH probe while keeping the cost low, a 3130 CMOS op-amp give […]
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