Crystal Pulling Schematic Circuit Diagram

In microcontroller circuits, quartz crystals provide the highest accuracy for keeping everything on frequency. With frequency and time measurement (and for commissioning master clocks) fine adjustment of crystal oscillators may also be necessary, so we will now investigate in detail how crystal frequencies can be ‘pulled’. Although we have taken the ATtiny25 AVR microcontroller from[…]

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PIC RJ-45 Cable Tester Schematic Circuit Diagram

This RJ-45 cable tester automatically checks cable continuity and tests the connection configuration. Each of the eight connections is checked independently and short-circuits are detected.   The circuit can be built using either a PIC16C62B or a PIC16F72. This microcontroller was chosen, as it has 22 input/output pins. Each RJ-45 socket uses eight input/output pins,[…]

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ECG amplifier circuit using ic 741 Schematic Circuit Diagram

Instrumentation amplifier using an opamp An instrumentation amplifier is a kind of differential amplifier with additional input buffer stages. The addition of input buffer stages makes it easy to match (impedance matching) the amplifier with the preceding stage. Instrumentation is commonly used in industrial test and measurement application. The instrumentation amplifier also has some useful[…]

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4-digit counter module

This compact four-digit digital counter is suitable for any application, such as clocks, frequency meters, digital voltmeter, tachometers, stop-watches, scoreboards, etc. The counter module provides a reset switch and a carry output signal. The maximum count of the module depends on which version of the IC used: • the MM74C926 pulls its carry output high when[…]

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