65MHz frequency meter based on Microchip's PIC16F648A. Frequency reference uses temperature-compensated voltage-controlled crystal oscillator (±2.5 ppm VC-TCXO). Features unique gate control method and precise time algorithm (non-interrupt mode). Frequency measurement accuracy is 10Hz or 100Hz (selectable). Gate time (display refresh) is 0.1 second with real-time frequency display. Dual intermediate frequency design allows separate preset of intermediate frequency value and plus/minus mode without interference. Display driver uses dedicated LED display chip; digital tubes offer high brightness and low external interference. Equipped with 6-digit 0.56-inch digital tube display, automatic blanking of leading zeros, and eight-level adjustable brightness. Simple circuit design with reasonable structure; two-button control for easy operation. Various settings are automatically saved and can be recalled upon power-up.