This recording was made without the use of a microphone. The output of the four radios is fed through the small mixer then directly recorded onto the sound track. This eliminates the effect of speakers, microphone and the room on the sound you hear. The only differences are because of the radios themselves (and their settings and adjustments). I use WWV at 15000 kHz in the final comparison and carefully adjust each radio for the best sound. One radio clearly cannot keep up. Not surprising since the other three radios are considered some of the very best receivers.
Order of Mixer Controls
Collins R390A, Hammarlund SP600, Grundig Satellit 800, Panasonic RF-3100
