The AMMA-2, the new digital AM modulation monitor from Belar, may look like an ordinary piece of broadcast equipment. It’s one rack unit tall and has the typical buttons and LEDs on the front panel.

First I’ll tell what you already know. Back in the day, AM broadcasting was king and FM was commercial-free. Things changed in the 1970s as FM grew in popularity. Here we are 40+ years later with many ...