1 GHz GDO Frequency Counter

thingiverse

I bought a KKmoon Digital Frequency Counter Module for my old Grundig GDO 701. This module is rated to operate between 1-500 MHz, but can be used up to about 1.1 GHz. High accuracy below 500Mhz, test results above 500 MHz are only approximate! Operating voltage: 9V, powered by a 6LR61 alkaline battery. The box can be optionally printed in PLA or ABS with the usual settings. Support required! The back plate can be mounted with four small screws, and there is also four holes forneodymium magnets for magnetic attachment to GDO. Update: I've added a coil to which you can attach an SMA connector. A few turns of thin copper wire should be wound over the bobbin and connect to the SMS connector. The frequency of a GDO or other oscillator can be measured with this coil using loose inductive coupling.