There are 3 inpust on this project a microwave (prescaled) input, an RF input and a TTL input. The microwave and RF inputs are AC coupled and terminated to a low impedance (around 50ohms). The TTL input is DC coupled and has a high input impedance. A progress-bar indicator is provided on the LCD for the gate timing.
Both the microwave and RF inputs have an additional feature : a simple signal-level detector driving yet another bar indicator on the LCD module. This is very useful to check for the correct input-signal level as well as an indicator for circuit tuning or absorption-wave-meter dip display (Lecher wires). This project designed by Matjaz Vidmar.
tag : RF counter, Microwave Frequency counter, PIC project source