Total posts : 45366
How does one make a “fool proof” Part 15 FM transmitter? As Rich and Tim have pointed out it matters not that a unit is “certified” by the FCC when the end user may inadvertantly cause the unit to exceed the allowed field strength by simply connecting a longer audio or power cable to the unit.
It’s not so much that the FCC needs to provide the “odometer” (read FS measuring device.) Instead, the certification criteria to maintain proper operation needs to be supplied with the unit as the manufacturer of the units seems to be lax or purposely vague in that area.
It would seem the only solution would be to produce an all in one, self contained, battery powered unit. No external connections which permit plugging in cables thus altering the performance of the unit. A built in MP3 player perhaps but this makes a live broadcast somewhat impossible.
For that matter, as it has been shown, simply changing the HAAT alters reflections which can reinforce the field strength at certain distances to the point of exceeding the permitted amount. Perhaps the NOUO’s should be based on field strength measurments at a prescribed distance (3 meters) to negate that effect. No more drive by measurements. Of course it goes without saying that some field strengths are obviously in violation regardless of where the measurement is taken.
As the general discussion has focused, the opinion seems to be Part 15 FM was not intended for hobby “broadcasting” and requests for increased range are the proverbial snowball in the devils hand. It’s going to take the creation of a class of service, licensed or not, to change the future of Part 15 FM hobby broadcasting.
An act of Congress you say? Yes!