Crystal Oscillator Tester 1Hz-50MHz Frequency Counter Meter with Case

Features: - This document describes the construction of small frequency counter with a cheap PIC microcontroller and a few seven-segment LED digits. - Frequency range 1 Hz ... 50 MHz - Five digits resolution (display for example kHz, MHz, or MHz) - Measuring signal amplitude can be up to 30 v - 4-40 m passive crystals can measure - Automatic range switching with different gate times - Optional addition or subtraction of a frequency offset (programmable) - Very low component count: a PIC 16F628, 5 7-segment LED displays, a 20MHz crystal and a few resistors - Optional (configurable) power-saving mode which automatically turns - The display off if the frequency didn #39;t change significantly within 15seconds - USB 5V or DC5-12V power supply can be used not soldered