It gives the tiny audio signal its first small boost. 4. Audio Power Output Stage Tube: 50L6 (or 50C5)
touch the metal chassis while the radio is plugged in. AA5 Radio Signal Flow
The AA5 is a radio. Because there is no power transformer, one side of the power cord is often connected directly to the metal chassis. It gives the tiny audio signal its first small boost
It "strips" the radio carrier wave away, leaving only the Audio Signal (the music or voice). AA5 Radio Signal Flow