I thoroughly enjoy reading RW, and Cris Alexander has written some great articles. His piece about the Potomac 4100 was no exception.
He mentions that it can be used to “facilitate compliance measurements (field strength, harmonic level and spectrum occupancy).” I am concerned the phrase “facilitate” may be confusing with regard to spectrum occupancy “compliance.” Though it could be used as a reference, there are key features/specifications it lacks in order to prove compliance with FCC (NRSC) requirements. This means it would not be acceptable to use the PI 4100 for the annual FCC required AM occupied bandwidth measurements (NRSC compliance measurements). The most obvious is the lack of a 300 Hz RBW (resolution bandwidth) option. The minimum resolution is 1 kHz RBW.
The specifications do not indicate it has the 10-minute peak hold capability, which is also an important requirement.
The meter would be a great purchase for someone needing a new one with many capabilities, but not to perform NRSC compliance measurements. I just want to save anyone the disappointment of finding out the expensive new meter they bought can’t be used for their NRSC measurements, especially if that was one of the major justifications in making the purchase — or worse, inadvertently subjecting themselves to a FCC fine for noncompliance.
Del Dayton
Dayton Broadcast Engineering
Eau Claire, Wis.
