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Amazon.com: Liyafy 1Hz-50MHz Crystal Oscillator Tester Frequency Counter Tester Measuring Meter Case Durable DIY Led Kit : Industrial & Scientific
![Ootdty 1hz-75mhz Frequency Counter 7v-9v 50ma Diy Kit Cymometer Module Tester Meter - Frequency Meters - AliExpress Ootdty 1hz-75mhz Frequency Counter 7v-9v 50ma Diy Kit Cymometer Module Tester Meter - Frequency Meters - AliExpress](https://ae01.alicdn.com/kf/HTB1vL8AAyCYBuNkHFCcq6AHtVXa1/OOTDTY-1Hz-75MHz-Frequency-Counter-7V-9V-50mA-DIY-Kit-Cymometer-Module-Tester-Meter.jpg)
Ootdty 1hz-75mhz Frequency Counter 7v-9v 50ma Diy Kit Cymometer Module Tester Meter - Frequency Meters - AliExpress
This document describes the construction of small frequency counter with a cheap PIC microcontroller and a few seven-segment LED
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Amazon.com: Ranjaner 1Hz-50MHz Frequency Counter Kit, DIY Module Board for Oscillator, Crystal Measure Frequency Meter Accessories : Industrial & Scientific
![Amazon.com: Liyafy 1Hz-50MHz Crystal Oscillator Tester Frequency Counter Tester Measuring Meter Case Durable DIY Led Kit : Industrial & Scientific Amazon.com: Liyafy 1Hz-50MHz Crystal Oscillator Tester Frequency Counter Tester Measuring Meter Case Durable DIY Led Kit : Industrial & Scientific](https://m.media-amazon.com/images/I/61EecLIPQ9L.jpg)