Free electronic circuit design and schematic diagram
This is a Electrostatic transducer for ultrasonic measurement circuit. This circuit uses the LM1812 ultrasonic transceiver. Transducer x1 and LM1812 will transmit a burst of oscillations. Then the return echo is listened by using X1. The LM1812 detector will generate a pulse of the same width as the original burst when the X1 receive an echo of sufficient amplitude. If […]
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We can construct a tachometer using the TC9400 in the F/V mode to convert the frequency information (RPM) into a linearly proportional voltage. Then we can compare this voltage to one of “n” comparators (on this example using 8). The respective LED lights up and will continue to stay lit as long as the voltage exceeds the trip point when […]
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Simple phase shift measurement can be done by squaring both the measured and the reference, then compute the difference of the two signals. The accuracy of the circuit shown in the schematic diagram below is 1% UP to 2000 cps. This circuit is used in computers and for high speed analog instrumentation. Negative value for zero phase shift is indicated […]
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For RF (radio frequency) transmitter experiment, watt meter is useful for optimizing the transmitter circuit. A simple RF watt meter circuit is shown in the schematic diagram below. Because circuit is not frequency sensitive, calibration is accurate on all HF bands. The sensitivity is affected by meter movement, number of turns in primary coil, and resistive voltage driver. Pots can […]
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Any frequency below 100kHz will be converted into an output voltage by TC9400 frequency-to-voltage converter. The TC9400 is linear to the input frequency. The equivalent frequency will be displayed on an analog meter. Here is the block diagram of the system: A frequency divider in front of the TC9400 can be used to scale the frequency down into the 100kHz […]
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If we want to record very low frequency or DC signal on an audio recording system, we have to convert the DC/low frequency signal into the spectrum of audible sound. The figure of DC response data recording system is shown below. We can record low-frequency analog data (DC to 10kHz) anywhere, store, and then reproduced. The frequency spectrum of the […]
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The TC9400 converts the analog input (Vin) ito frequencies (10Hz to 100KHz) which can be used to modulate an RF transmitter in a telemetry system. At the other end, The RF signal is picked up by receiver and it’s demodulated back into the 10Hz to 100KHz spectrum. A count linearly proportional to the original analog voltage (Vin) is given by […]
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