The TFT FM Modulation Monitors are good monitors. But the peak indicator circuitry will often overshoot when aggressive audio signal processing has been applied to the audio. This overshoot can fire peak indicators even when no over- modulation actually occurs, causing as much as 17% over-indication! To turn off the peak indicator, you must reduce the modulation level below the maximum legal limit. This costs loudness!

Our modification replaces the original demodulator lowpass filter with a computer-optimized, linear-phase design to reduce the adjacent channel interference. An integrator feedback loop in the demodulator signal path achieves direct-coupled performance. The modification virtually eliminates monitor-induced overshoot. Modulation - static or dynamic - is measured to better than ±1% accuracy, even at remote locations and with the most aggressively- processed composite waveforms. The peak indicator circuitry is temperature-compensated for long-term stability. Group delay equalization throughout the frequency range of the stereo baseband maximizes stereo demodulator performance.

Fundamental design improvements achieve these benefits. There are no trick circuits that can conceal illegal modulation. More costly add-on devices that allegedly allow increased peak deviation can ignore real peak over-modulation. Most add-on modulation meters measure modulation far differently than the FCC monitoring truck, resulting in un-indicated peaks, over-modulation, and potential FCC forfeitures!

Our modification ensures compliance with all current FCC rules and regulations, yielding accuracy 500% better than that formerly required by the FCC. Baseband response is flat and phase-linear to 100kHz, so all sub-carriers are measured correctly.

Take the guesswork out of modulation measurement. Efficiently use the legal modulation limit by avoiding under-modulation with complete confidence. Eliminate the possibility of FCC citations. Maximize loudness without compromise and the expense of a complete new monitor.