We all know the other Part 15 radio broadcasting site that actively looks for FM stations violating the rules. They're pretty strict about it - no holds barred.
So, I had to laugh when I saw a recent post over there that talks about the webmaster getting a new roof, and having to relocate at least 3 AM transmitters (including the Talking House Range Extender) from said roof. He was talking about putting one transmitter on a mast beside the house.
Unfortunately, you can't have an elevated Part 15 AM installation without having a long ground lead - remember, that a Part 15 antenna system, consisting of radiator, ground lead (to an RF ground which doesn't radiate) and feedline (which may or may not radiate) can't exceed 10 feet or 3 meters.
There's just no way around it. If you use a short ground lead to connect to something metal that is also elevated, it will radiate, increasing the effective length of the antenna and violating the rules.
And if you don't connect a ground lead, your transmitter won't work very well. If it does get any kind of range, then some other connection is acting like a long ground lead (either power or audio).
Some might argue that that interpretation is overly restrictive. Yes, it's meant to be. The intent of the short antenna system on AM is to restrict range, much like the intent of limited field strength for FM is to restrict range.
If you're going to be exacting in your analysis of an FM signal, and an FM transmitter installation, you should be just as exacting for an AM signal and an AM transmitter installation.
Anything else is hypocritical.
... getting a new roof, and having to relocate at least 3 AM transmitters (including the Talking House Range Extender) from said roof. He was talking about putting one transmitter on a mast beside the house... you can't have an elevated Part 15 AM installation without having a long ground lead -
...There's just no way around it...
However, the Range Extender can and is designed to be raised - and has been certified compliant when used with the talking house.
Why it was granted certification I couldn't tell you, but the fact is it's certified and has been for decades.
You might say its grandfathered in.
Yes, I am aware of the Range Extender and its tenuous certification. From what I understand, the manufacturer successfully argued that the Range Extender unit comprised the final stage of the transmitter, so the feedline didn't count in the overall antenna length. I don't think they would get away with that today (or even yesterday).
However, the Extender unit still requires a ground to work effectively (there is a ground lug on the unit), regardless of being designed to be elevated, and that ground + its radiator (antenna) has to follow the 10 foot rule.
I personally have nothing against someone who elevates an AM transmitter, and lets the FCC decide if it's compliant. What I do have issue with is someone who is so strict with FM rules, to the point of potential pirate accusations towards anyone using Part 15 FM (except, of course, his Forum members), while clearly and knowingly (since he does claim to be THE expert) pushing the limits of the AM rules.
Yes, I am aware of the Range Extender and its tenuous certification. From what I understand, the manufacturer successfully argued that the Range Extender unit comprised the final stage of the transmitter, so the feedline didn't count in the overall antenna length. I don't think they would get away with that today (or even yesterday).
However, the Extender unit still requires a ground to work effectively (there is a ground lug on the unit), regardless of being designed to be elevated, and that ground + its radiator (antenna) has to follow the 10 foot rule.
There may be a ground lug present on the atu, but it's intended designed to achieve is ground via its feedline and on through to the talking houses 3 prong outlet where the transmitter plugs in. -Thats how its supposed to be installed - no?
I dont think its manual says to connect a ground lead to the ATUs lug for installation does it? - Did the original TH ATUs have their own external ground lug too? I'm not sure, but using It would alter the gound path it was dedigned take, thus void certification.
Don't ground to that lug with an elevated install and your good - Right?
Isn't all this correct? Or have I got something misconstrued? -
Both the original and the newer Range Extender have ground lugs. I owned an original one, well before I realized that such a setup was not compliant in Canada.
As I recall, the manual states that the ground lead for the lug and the radiator can't be greater than 10 feet.
The Range Extender may achieve a ground through the feedline and the 3 prong cable. So for that one transmitter only, you would likely get decent range not connecting the ground lead.
However, it seems to me that the FCC not only looks at certification, but at actual use. We've just talked about this recently. That's why they'll measure the field strength of an FM transmitter during use, and even if it's certified, they can cite you if you are over the limits. They don't even have to see your transmitter to cite you. I would think that the same thing applies to AM, if in a slightly different way. If you're getting an effective antenna plus ground greater than 10 feet through the feedline, then maybe the FCC would have something to say about it, even if the setup has been certified. Particularly if the field strength of the installation is above what they would expect it to be.
Anyway, that only applies to the Range Extender, a somewhat unique case, and not to the other transmitters that were located on the rooftop in question, which would all have to have had long ground leads to operate properly.
I read the post you are talking about. Hes moved only what was a single unit from the roof - not multiple. It's unclear to me what he moved from the roof , was it a transmitter itself or it's atu? - I get the impression its actua)y the atu that hes moving to the mast on the side of the house. He then says he has three other transmitters also, but there had been only one on the roof.
It's really hard to tell what's going on from just the first post without readng the rest of the thread (which I can't see), but I would really have a hard time believing Bill would install an non-compliant transmitter and plaster that information publically on his forum- there's just no way. This is the same guy who has cut his whip shorter on one of his Rangemasters so he could raise compliantly raise it off ground. No... I think your reading things into his post that it doesn't actually say.
But then again, he does show pictures of that transmitter some guy operates at an airport in the stati OP n reviews section of his website. He praises the station but doesnt mention anything about the raised install cleary shown in the review.. who knows, maybe it's not using a ground lead.. But I have a hard time believing Bill himself would install a transmitter without being compliant.
I'm not trying defend him really.. I think he's a major dick, but I also think he's diehard part 15 compliant.
...However, it seems to me that the FCC not only looks at certification, but at actual use..... ...If you're getting an effective antenna plus ground greater than 10 feet through the feedline, then maybe the FCC would have something to say about it, even if the setup has been certified. Particularly if the field strength of the installation is above what they would expect it to be...
Well yeah, thas always been the case with the Talking House (and its range extender), both devices at face value appear to be non-compliant units - It is their certifications that make it compliant in spite of the rules somehow!!
So yeah, plug that transmitter into an 8 story apartment building and you turn it into an 8 story antenna, it results a field strength very excessively strong resulting in an NOUO (as is exactly what happened.) ---- BUT 15.219 has no field strength limit, which is what the controversy had been all about.. But that problem is only applicable to to the Talking House because of its controversial certification.
I stand by my original interpretation of his post. Multiple transmitters on the roof, had to remove them prior to roofers coming in, now needs to find places for them as he doesn't want to make holes. If he clarifies things, I'm certainly willing to change my mind. But then, who will know, as no one other than members can see subsequent posts.
Based on previous posts, I can see him having roof mounted transmitters. After all, this is someone who has talked about the differences between being "strictly compliant" and compliant with AM transmitters. I didn't know there were any (compliance, after all, is compliance), but then, who am I?
Based on previous posts, I can see him having roof mounted transmitters. After all, this is someone who has talked about the differences between being "strictly compliant" and compliant with AM transmitters. I didn't know there were any (compliance, after all, is compliance), but then, who am I?
You've got a point there.
Another post over there just proved me right. It was in reference to the installation of elevated transmitters, and lightning arrestors. A statement was made to the effect that it was up to the individual operator to decide whether they wanted their installation to be "by the book" compliant. I thought that was the intent of all legal installations. It was also mentioned that using a particular type of arrestor would stop a long ground lead from radiating, so the operator would have to live with decreased coverage.
It's really amazing the differences when they discuss Part 15 FM vs Part 15 AM. With Part 15 FM, according to them, you have to be "by the book" compliant all the time. With Part 15 AM, I guess they feel it's OK to be sort of compliant. Maybe. If you feel like it.
@artisan-radio Yeah I started to comment on that... That's an old post going back to KENC citations days and that's what that discussion had sprung from. A few different chokes had been experimented with and even Keith Hamilton designed and redesigned one and submitted to FCC but it was denide certification of conformity.
But anyway, it seems obvious that old thread had been revived in reaction to his reading of this thread here.. but most of us over here (myself included) cant see what comments were made tha revived that thread, but we can be sure it's got something to do with us "minions" over here spewing misinformation and it's all because basically we are all against him.
As for HBs leader having the tendency of talking out both sides of his mouth in regard to compliance.. Yeah, well that's pretty undeniable. But really, in my honest opinion... I'd be surprised if any more than about 10% of existing pat 15.219 installations were really 100% compliant. So, you know.. cant really.. you know...
Oh! by the way, meant to mention it the other day. The most likely scenario on Bill's rooftop transmitter or transmitters is that he did not include a ground lead (if used) at all.
We all know you don't absolutely need one because in its absence it will find another path (the audio and/or power cable), but that's not part of the 3 meter antenna and ground lead (if used), therefore compliant.
He simply installed without ground leads.