Total posts : 45366
mlr wrote “By taking Part15 into the realm of the over-extreme technical discussion, some people with power to do things, have been using *your* discussions to shut down stations. Congratulations. Some of your technical meanderings have now caused Part 15 to come under the microscope again, and may now be changed to include the highly technical specifications that we have, until now, had the freedom to experiment with.
Things that will likely be affected: Base loaded antennas – we’ve been allowed to use them because the fit within the top down measurement of under 10′. Grounding – we’ve been allowed to ground our xmitrs to the mast so far – now it looks like the mast may be included in the measurement. Some Type Accepted xmitrs will no longer be accepted – even the ones you just payed a grand for. Some kit guys are going to go out of business. Visits and letter are coming to a part 15 station near you.”
We can be certain that the FCC has known even prior to issuing the rules for Part 15 that the entire conducting path from a Part 15 AM tx chassis until that path enters the earth will radiate, and add to the permissible 3-m length of the radiator. Of course that also pre-dates any post about that on this board and elsewhere.
It is understandable how that point of physics is an inconvenient reality to some Part 15 operators, because it limits the performance of their systems.
Part 15 rules may appear simple, but that doesn’t mean that the underlying science is simple, or that simplistic beliefs about Part 15 are appropriate. The true functioning of a Part 15 system takes some effort, objectivity and education to understand.
Instead of suppressing such information, one might take a position that making it more accessible would be an important function of these boards — especially if it helps someone avoid “FCC problems.”