This is one of the great threads, started by Radio8Z with his thoughts on "Discouragement." Everyone's comments showed such a strong allegiance to this second smallest hobby in the world.
The first "discouragement" listed was the failure to meet expectations, perhaps for broadcasters who expected better range. But for me, my expectations from part 15 are met completely, as I am able to enjoy a private radio station around the immediate "campus." I call my yard a campus, that word is not copyrighted.
Neil's reasons for enjoying the hobby make a good checklist to learn where we stand:
REASON 1: Personal Control. Totally! With "other people's radio stations" the only control is the off/on switch;
REASON 2: Technical challenge. If so inclined, the technical challenges can fill hours and years of pleasurable time. If not so inclined, it may not work out;
REASON 3: Fun to produce. You bet. Program production is so much fun that if I gave it up I would do a radio program about it;
REASON 4: Limited range. Well, that's the biggest disappointment for many, which takes us back to our "expectations." But most of the time for me I prefer limited range. There are two exceptions: I was disappointed when the signal wouldn't reach a neighbor woman's radio three-blocks away, and at times I'd like to listen to a program all the way to a shopping center a mile away, and those two situations have no obvious solutions.
Do you want to know the first smallest hobby in the world?
Art projects made from washing machine lint.
For me, the drive to continue is doing. You know, actually going outside, setting up some ridiculous thing that resembles some sort of antenna, even though it was salvaged from a previous holiday season, and conducting field tests of the ridiculous apparatus.
There is such a thing as a mailbox antenna..I built one, while ignoring all the naysaying.
The best part..is simply using the imagination and building something in the real world no matter what the number crunching or virtual world simulation programs say. I found many times that the simulation doesn't always jibe with reality.
Another quote from Stark Trek..."We learn by doing", Kirk - turbo lift with Savik - The Wrath of Khan.
To me what becomes discouraging is constantly hearing, reading the "it's not possible" or "it's not legal" or "the simulation says it wont work" blah blah.
If I wanted to have some simulation tell me constantly I cannot do it then I would fire up my own simulation programs and let them to the talking...but since I don't, why would I want to hear it from someone or some other simulation program!
It's a hobby, not a crucial activity that will make the sky fall and cats live with dogs while singing to birds.
RFB
IT'S NOT LEGAL can certainly be taken to extremes, but I do think it's important to let those who read the Forums for information to know just that. And that you're taking on the associated risk of being shut down if you proceed along a certain path (whatever that path might be).
Part 15 FM always seems to have a lot of misinformation swirling around it. When it's dead simple. In the U.S., if you're getting more than 200 feet range to a cheap portable radio, or 800 feet to a sensitive car radio, you're probably exceeding the maximum legal field strength for FM. Probably, not a certainty of course.
If I wanted to have some simulation tell me constantly I cannot do it then I would fire up my own simulation programs and let them do the talking...but since I don't, why would I want to hear it from someone or some other simulation program!
Understood, but just to note that when using modern mathematical analysis techniques and accurate operational parameters to determine the performance of a "Part 15" system, this ALWAYS will show the real-world performance of that system -- even though such performance might be less than desired by some operators.
The FCC is getting dumber by the minute. I own rural property that is 1000 ft across. the part 15 transmitter will not cover that distance because of trees etc.Purchased a 1 watt slug for bird watt meter and found out that the FM25 transmitter was putting out .02 watts and purchased a 1 watt adjustable transmitter the low setting is .05 watts. have found that .1 watts is a good power output for several blocks. The problem that I see with part 15 is it does not address our current time. When it was written appears 1946 there was vacuum tube circuits and could not become compact.The FCC does not even want to update the rules to 87.8 to 108 mhz as is the current FM band.
Antenna used is a 5' dipole and the balun is 75 to 300 ohm used on TV antennas. works really good.
My interest is not to become a broadcaster and use for my entertainment. Stay below the radar is my suggestion.
In my humble opinion, the statement that a computer simulation "ALWAYS will show the real-world performance" is not merely wrong, but also nutty.
The FCC is getting dumber by the minute ... have found that .1 watts is a good (FM) power output for several blocks ... Stay below the radar is my suggestion.
Everyone subject to FCC rules is free to operate whatever unlicensed AM/FM system they wish, based on their understanding of Part 15, and their desire to avoid FCC actions.
But just to note that an FM system using a transmitter output power of 0.1 watt, and a matched 1/2-wave dipole transmit antenna will produce a field intensity FAR above the FCC limit given in Part 15.239.
There are many examples of FCC citations (NOUOs) shown in the database of the FCC Enforcement Bureau to illustrate this for systems using transmitters rated for much less than 0.1 watts.
Mr Roos posted: In my humble opinion, the statement that a computer simulation "ALWAYS will show the real-world performance" is not merely wrong, but also nutty.
I didn't state that any/every computer simulation always shows real-world performance.
That result depends on the coding of the computer program, the accurate definition of the parameters of the analyzed system, and the skill/experience of the operator.
Repeating my original post on this subject...
Understood, but just to note that when using modern mathematical analysis techniques and accurate operational parameters to determine the performance of a "Part 15" system, this ALWAYS will show the real-world performance of that system -- even though such performance might be less than desired by some operators.//
[Mr. Fry}* has generated and posted some of his own NEC simulations that gave absurd results. I note, for example, his simulations of helical antennas posted both on this website and elsewhere.
*[edited by radio8z]
I think perhaps wildbill is making the point that the FM signal he is generating is well within the confines of his self-owned property.
It would seem to me that FCC compliancy readings could only be taken out at the boundaries of the property, in space belonging to "the general public."
"The problem that I see with part 15 is it does not address our current time."
Most of the rules still on the books are from the 1930's and are so out of the times it's ridiculous. The only thing that is current is the morphing of what was once easier to obtain is now more difficult than ever. It's no longer about interest or serving a purpose, its about making the biggest fattest bottom line possible no matter what.
Auctioning off spectrum like chunks of real estate to the highest bidder. Basically cutting off public access to public airwaves but only to the wealthy and big corporate conglomerates. Hardly anything in the public interest.
When did the public declare the public airwaves to become the property of the government and given the right to auction off spectrum and make money off of something that is supposed to belong to us! Where is my check?!!
Pfft.
RFB
When I first heard of the "selling" of "public airways" I figured there would be a "class action lawsuit" to determine that the gov couldn't sell "OUR" property, but........ snore, snooze.
Carl mentions a scenario where a large property is involved, covering far more than 200 feet. Now here is an interesting question.
Suppose this person sitting on 50 acres decides to put up an FM transmitter to cover most of that 50 acres of private property.
Obviously 11 nanowatts wont cut it, yet 11 nanowatts is what is necessary to hit 250uV at 3 meters.
Now throw in another curve ball. This person sets up their system so that coverage is confined well within the property line. In fact they set it up so that the signal is only covering about half that acres from the center, leaving about 25 acres on all sides that does not get coverage.
Now the FCC cannot just walk onto private property without a warrant, be it they are investigating something or not. Since they will not detect the signal at the property line, does that mean the operator should cease operating their 25 acre FM coverage in a 50 acre ranch just because of the useless 200 foot "tradition" rule?
I think not. That person should have the right to cover their entire private property with signal. If they keep it within their property line, what's the problem? Who's gonna get world destructive, such harmful interference from that?
The rules are certainly not clear or precise. They (Part 15), is pretty much a blanket one cover fits all set of rules, not allowing for variables as allowed in other services. Obviously the intent is NOT to prevent interference, but to silence individuality and sovereignty and freedom of speech.
He who has the gold does indeed make the rules. Pitty no one has understood yet that those who make the rules usually are the ones violating them or totally ignoring them.
RFB
YES, RFB, and furthermore......
I have today decided that inside the house it is LEGAL to boost an FM signal if necessary to reach every room within the house, so long as the field measurement out at the boundary of the property doesn't exceed the micro-mini nano size.
To prove it, I plan to do it.
Not this year, though.
Major thread drift but that's OK since it is fun and the topics are interesting. It is one of the reasons I value this forum.
RFB mentioned the oft heard purpose of the rules is to prevent interference. I am going to make the context for this post to be interference due to spurs and harmonics. If the original intent of the FCC allowing low power broadcasting was to enable the use of phono oscillators then this was a real concern.
I used to have a 1930's vintage phonograph with a phono oscillator built in the base. Interestingly, the filament of the lone tube and the motor were wired in series which is a clever way to reduce the line voltage to power the low voltage filament despite the motor load giving a barely predictable filament voltage. To the point, this thing put out a RF signal that was mostly trash. The waveform viewed on a scope was clearly distorted and harmonics could be heard up to the limit of my short wave radio which was 20 MHz. The modulation was terribly non-linear. The frequency was set with a mica/metal sandwich variable cap. and it drifted quite a bit with time and movement around the antenna which was a couple of feet of insulated wire. It made sense to limit the power and antenna to minimize the chance of problems with this equipment.
Now forward to the present where it is very easy to produce broadcast specification frequency stable AM signals with almost unmeasurable harmonics and no spurs so this calls the question about interference. The only important interference would be co-channel and all Part 15 AM operators, I assume, go out of their way to avoid this to avoid trouble but also with the realization that their own range is diminished by a co-channel signal.
Which brings us back to RFB's post where he mentioned what is probably the real modern reason for the limits which is to keep micro-broadcasting contained and discouraged. Unfortunately, if the rules are revised and this is the intent then even more range restrictive rules will probably result.
Despite this I continue to enjoy my Part 15 AM activities and refuse to be discouraged.
Neil