Submarines, spherics and Radxa Rock

I’ve tried for fun ,to record with a cheap USB Sound Card, a Radxa Rock Board with a custom kernel (added some audio and USB modules) running  Ubuntu Server  and the Explorer E202 , some stations  in the VLF band. We usually monitor them in  Turin observatory for SID correlations ( ) The VLF receiver […]

Efratom M-100 : First View and Test

 What are we talking about? Today I’ll talk about this magnificent little device found on eBay : the  Efratom M-100.First of all, what is a Rubidium Frequency Standard?  It’s an atomic clock.Just in the 80-90 they were such  an expansive units! The working mechanism is fascinating. It uses the hyperfine transition of electrons in rubidium-87 atoms […]