With regard to retro test gear, one’s thoughts tend to those Nixie-adorned instruments of yore, or the boat-anchor oscilloscopes that came with their own carts simply because there was no other way to ...

[Scott] built this frequency counter using less than $10 in parts. It’s set up to meter frequencies in megahertz which is fitting since he’s planning to use it with his radio hardware experimentation.

The device is a simple, small, and cheap frequency meter with out any hard to find components to be able to measure frequencies up to 40 MHz while having below 1% errors. Most of the analog and ...

This sound frequency meter circuit is simple to build and can be constructed in a portable format. In can measure frequencies with a minimum level of 10 mVrms and a maximum frequency of up to 100kHz.