In the years since this forum started, I have noticed a trend.
New guy asks about his rig. a few people get snarky because the new guy has this perfect setup, the rest are divided into three groups.
First group says "Ground mount, no radiating grounding!"
Second Group says "Get it up as high as you can, ground to whatever is available."
- both of those groups suggest things like expensive monitoring gear, lawyers, and field engineers. Both of these groups are happy to produce a ton of documentation, graphs, and charts showing the legality of X and Y.
Then there is that last group - a very small group.. maybe 2 or 3 people, who say "Under Part 15, the FCC do not expect the average Joe to have access to this stuff, and they will give a little leniency, as long as you aren't clearly out trying to do something sneaky."
You all know by now that I am not an RF or audio engineer by any stretch of the definition. I have run a few Part 15 stations though. It has been my experience that the FCC are going to come kicking in your door unless you do something outrageous.
I know of 4 part15 stations that run multiple transmitters, all mounted high, all grounded to mounting masts, all the masts grounded to something like a cold water pipe or electrical ground, and all have been operating for over 3 years. One has operated for almost 10 years, and the oldest I am aware of running a home made transmitter has been running since the 80's. None of these guys has ever seen so much as a letter from the FCC.
I know folks who have been contacted, and I myself have been inspected. Once they initiate contact, you tell them the FCC ID you are running, or you tell them the model of the kit, tell them where its mounted, and don't go into technical details. "I have an SSTRAN AMT3000 with a 9 foot copper pipe antenna, the thing is mounted, transmitter and antenna together, on my roof on the mounting bracket that use to hold my dish network dish." Normally, from the folks I know, this is enough. In my case, the field guys actually lived a few blocks from my transmitter site, and came over and took a look. At this time, I was running my gittings, with the manteca magnum, mounted to a ratshack 10' pole (now I only see the 5' poles at ratshack), that was attached to my fence. This whole mess was grounded to my cold water pipe using some pretty heavy copper wire from the pole to the pipe. All they did was ask me "Describe this setup to us." which I did.. they glanced at it (no measuring gear, by the way).
I had great FCC folks. Not everyone will. This is just my experience.
Why this long diatribe? Well, I have noticed that we, as a group, have deterred at least one person from part15 radio, and now there is a nother guy who has this awesome setup, great support from his town, his local media outlet loves him, the citizens of the town love him, but he is terrified to stick a hamilton on his roof. Not only has he got this great town support, but his roof is made of metal.. seriously; how many of us would give a body part for this setup? I, myself, am extremely excited for this guy. I think if he does go through with it, he will end up with a killer station.
Enjoy your portrait of the type people found in part 15, and add one more type.
Every so often a new member starts by saying that he wants to build a part 15 station right out of the box, no technical complications, just plug-n-play.
I knew one of these people in personal life, a neighbor who wanted an FM transmitter so she could listen to internet radio inside her house, but she kicked the whole idea out the door when the C.Crane FM transmitter didn't do what she wanted. I told her that with some trial and error we could get it to work, but she was done, in her mind, things either worked, or they didn't.
When it comes to FCC inspections, my big question is, who complained and why did they complain?
There is always a possibility of a negative visit from the FCC but these are rare and this threat should not deter anyone from operating a part 15 AM system. If one follows the rules there is little chance of trouble.
The greatest contention seems to be the length of, and yes, even the definition of the ground lead. Elevated transmitters with ground leads may be OK with some inspectors and not OK with others as evidenced by mlr's experiences and those who have been cited for ground length problems. One can then conclude that sometimes long ground leads are OK and sometimes they are not. From this, an operator can decided what to do.
My choice is to eliminate the ground lead concern by mounting the transmitter at ground level. There may be other things an inspector would not like but it won't be the ground lead length.
Neil
Well, if some facts deter someone from starting a Part 15 station, then they weren't all that interested in the first place. Just my opinion.
I believe in knowing all the facts and risks. Then you make your own decision.
I have no experience with the FCC, living in Canada. Here, I know of no one who has been told to cease and desist because of a long ground wire. The few that I do know of were obvious pirates, running transmitters many times over the legal limits.
But in the U.S., things are a bit different. Most of the time, the FCC deals with obvious pirate transmissions. But there are instances when they take a hard line stance on meeting the Part 15 rules exactly. I'm sure there is a lot of leniency. But there might not be. People need to know that, and make their decisions accordingly.
I totally agree with Neil and Artisian; on Artisian's note, I would would say maybe we need to be a little gentler with the new guy.. That was really the point 🙂 But I talk and type way too much, so it ended up as a novel.
I like the idea of telling the new guy "3 meters, 100mW" - but to be fair I would also tell them "The grounding thing is a grey area, no one will define it, so we have to use our judgement."
For me: I have no issue with grounding my rig to the mast - I really do not want lightning following the feed line and blowing up my house (yeah yeah.. overly dramatic). If the FCC asks me to remove that ground lead, I will. I will also get them to provide me with the actual definition of the ground lead issue. Thats all 🙂
FRIENDLY with slow and patient operation when requested, friendly advice and counsel to the beginner, kindly assistance, co-operation and consideration for the interests of others. These are the hallmarks of the amateur spirit.
There are a number of fairly technical people here. Technical can sound unfriendly to some, but I don't believe any discussions so far have been meant in that fashion.
But you're right, mlr, I like your description of the grounding problem. Simpler is sometimes better, especially with first timers.