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An Arduino frequency counter

An Arduino frequency counter by WA5BDU       Introduction This is going to be a fairly long description of the frequency counter and the ICs and circuits that make it go. That’s for people who might want to roll their own or modify this one. Otherwise, if you’re mainly interested in building one, gloss …

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Programming the Si5351a synthesizer

  What is being discussed here   I’m going to discuss how a program, or my Arduino program specifically, calculates register values for the Si5351a to put it on a specific frequency. I’m not going into details of how the register values are formatted into bit fields and actually sent to the chip via I2C. …

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An Arduino Si5351a quadrature VFO controller

Front view of the VFO. The display is indicating the Receive and Transmit frequencies, the step size, and the current mode. Pushbuttons PB1, PB2 and PB3 are surface mount type soldered to a bit of circuit board material.   Here’s a full-featured VFO I built around the Si5351a synthesizer IC and an Arduino controller. I’ve …

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