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June 13, 2019 at 2:20 pm #111523
And Mr. Legend:
The laws of physics and where THE ELECTRONS come from and where they go is what determines the results.
The equipment just helps everything go in the right direction.
So take your time and don’t worry about the outcome.
The water table and ground conductivity are probably
unknowns, as well.
Brooce, Connecticut
June 13, 2019 at 10:06 pm #111525Hi everyone .
I have been reading this thread. No one really understood the reason why the FCC did what they did with this transmitter but after going over all the rule it was clear how the company was able to get around the rules. They really did not get around the rules they just read them very carefully and found a way to get the most out of a transmitter that no one had ever thought of before. By the end of this post you will know why they were approved.
I have been license for 40 years and I have worked with the FCC on many occasions.
I am not going to list each and every section of the FCC rules to try and explain this mess but just put it into plain English.
First off the Range Master and Procaster do not fall into this category since their antenna’s are coming straight out of them.
Ok the rules read that your antenna,feed line and Ground shall not exceed a total length of 3 meters.
Let keep this very clear and it has nothing to do with your final stage amplifier that cannot exceed 100mw DC input power.
Ok most the transmitters being made today have the final amplifier and your PI Network all in the same box . Some of the Pi Networks are design to tune your antenna. Keep it in mind you have the entire transmitter in the box. So if you come out of the regular transmitter now you cannot have an antenna that exceeds 3 meters with your feed line.
If you add a ground wire Then you have to subtract that from your feed line and antenna length.
Ok this is not your regular AM part 15 transmitter.
http://www.iamradio.net/range-extender-2.5.htm
This is how the company was able to get around this rule. They broke their transmitter up in to two sections.
First section being Audio stages,PLL synthesizer for your frequency and your final amplifier with no filtering or tuning section. If it had these then you could not run coax to an antenna.
Company was smart put a tuner that acts like you filter as well antenna Matching section in a separate box.
Now you are not running coax to your antenna but now your final filter and tuning section of your transmitter. This is why the filtering section has an antenna coming out of it. Since the antenna comes out of the filtering section and tuner section the FCC sees no feed line to your antenna.
What they do see is a connection between your final transistor and your filtering section that just happen to have a matching network.
So that coax can be as long as you want because it is not directly hooked up to your antenna but instead to your filtering and antenna network box.
If this transmitter had the feed line coming out of the filtering section and antenna matching network box to your antenna this transmitter would be shut down.
When they design this transmitter they really thought about how to get around the rule that says your antenna cannot exceed 3 meters in length in total length with feed line,Ground wire and your antenna itself.
The FCC could do nothing because it had meet all the current rules of the time this transmitter was being approved . Who to say later down the road there could be a rule added to keep this form ever happening again. I really doubt it will change but this is the First transmitter to ever have two sections to make it work.
Ok here is the big thing how tall is the antenna that come off that box.
If it is 7 FT then you can have a Ground wire 3 FT in length. If it is 8 ft tall then you can have a ground wire that 2 ft in length.
let just say you had this transmitter up 20ft in the air and your antenna is 8 ft tall.
Then you could run a 2 FT ground Wire into a RF Choke then from the RF Choke down to your ground Rod.
This is a legal set up. When I was talking with the FCC this was the only way they said that a transmitter mounted very high up in the air could have a ground wire that long in Length.
I have also been license for around 40 years in radio and I know these rules and I was in Constant communication with the FCC.
Now he bought the transmitter and if he sets it up by the way the instructions say then he will be legal in every way. At least you know how they were able to get the coax to the filter/tuner section. They do not see the coax coming from the transmitter to the Antenna.
They see the coax coming from the final output transistor to the filter/tuner section.
Your antenna comes off the Filter/tuner section box and has no coax between them.
This is the only reason why this transmitter set up was ever approved.
They broke the transmitter up into two separate sections. The coax is not recognized as feed line but instead just a wiring section to connect the entire transmitter together.
Does this now make any sense to everyone.
He still has to figure his ground wire length from the transmitter to the ground rod.
Now one more thing anything buried under the ground does not count as part of your ground wire length. This is why an 8 foot ground pole does not count as your ground wire length. It because it under the ground.
You can run ground radials as long as they are under the ground buried.
If you want to dig a bunch of ditches and bury a bunch ground wires under the ground go right a head . It very legal the FCC will not hold that against you. They look at them the same way as the 8 ft ground pole since they are under the ground.
I hope this is a real help and and clears up why the FCC approved that transmitter setup.
It is very legal by the rules that the FCC had set in place when this transmitter was being approved.
Thanks
.
June 13, 2019 at 11:13 pm #111530Sorry my post went a way that explain how the ISS Extender works and why it had been approved by the FCC but I am not retyping it all over again.
If it was removed then I am sorry if it offended anyone but I dont see how explaining how this equipment was approved by the FCC.
Anyways Not sure what happen but it been years since I posted anything on this site.
Ok Post has been put back up on thread.
Thank you
June 14, 2019 at 10:36 am #111537Well, I saw the post and it pretty well sums up the situation. I don’t know that I agree that we gain any salvation by using an RF Choke in the ground wire, though. I understand the merits of using a choke, but as a communications attorney I don’t see anything in applicable regulations allowing us to go long with the ground lead by using a choke. Not that it would necessarily hurt anything, either.
I think the real issue with ground leads is how such are defined under the law. There is certainly a lack of definition in the regs, but the FCC is subject to plain writing and plain language requirements. Look up ground lead in the dictionary. Limiting the length may not be nearly as restrictive as some would have us believe…
John
W9LWA
June 14, 2019 at 1:15 pm #111541Let’s not make this another long ground lead discussion. We’re wandering far off the intent of the original post.
June 15, 2019 at 12:19 pm #111546Hi
Well Did I mess up and erase the post by Accident ?
It really was not about the ground wire itself but how the company split the transmitter in to two different sections to allow for a coaxial cable to run between both units.
And was able to keep it legal .
That pretty much it.
June 15, 2019 at 12:21 pm #111548Hi
Sorry it posted twice on one of my post.
I will let you all get back to your conversation
Thank you
June 15, 2019 at 12:33 pm #111551Well, it was there long enough for me to see it and I didn’t see anything wrong. My only question was if you know something I don’t about the FCC taking an RF Choke into account in the ground lead measurement. I can see why they might, but haven’t found anything to indicate they have or will.
Thanks for your comments.
John
W9LWA
June 15, 2019 at 1:13 pm #111560Hi John
I have other transmitters as well. The FCC told me if I wanted to place a transmitter up really high then I needed to place an RF choke in line with my Ground Wire to make a DC ground connection for Lighting strikes.
See the rule says that you can only have 3 meter in total length this would count your Antenna,Lead wire(coax), and Ground wire.
In all this cannot be no longer than 10ft in length.
So lets say you have a 8ft antenna coming directly out of your transmitter.
This will only allow you to have a 2 ft ground wire. That 2 ft of ground wire the FCC see’s that as part of your radiated signal.
So if you want to have a longer wire than 2 feet you need to place an RF choke after that 2ft point. Since the RF choke stops all RF from getting through the FCC sees the wire after the choke as a non radiating wire.
Then you can have any length of wire you want after that choke. This is not in the Rules it was what I was told by the FCC and if I mount any of my Part 15 transmitter up very high in the air this would be a way I could provide a ground wire to them.
I really do not think the FCC going to do anything to anyone if you are mounted on a metal fence post and your ground through it.
Since this is very low to the ground. This is more transmitters being mounted very high up in the air.
Now I know of one individual who mounted his transmitter to the chimney of his home.
He had a power outlet added on the top of his home right next to the chimney .Since the Power outlets go to your house ground. He used that ground. He just ran a 10 guage
wire from the transmitter to that out let ground. The wire was bright green and only measure around 18 inches. He Labeled it ground wire. The FCC never gave him any problems since they did not count the house ground . They were not going to tear up his house just to see how long the wires were to the house ground rod. They only counted that short 18 inch bright green wire as his ground wire.
Anyways this was what I was told to do by the FCC on my set up if I need to extend my ground wire for a DC ground.
I hope it helps out a lot.
Ok it looks like my old post came back up.
thanks
June 15, 2019 at 1:43 pm #111565Ok I said enough and do not want to offend anyone in anyways.
I have only told you the way the FCC told me how to set up my ground system.
This is for anyone who want to know the Choke size I was told to use was a 1 mili henry
or larger should block all RF signal past my ground wire of 2 ft in length.. My ground wire is 2 ft so anything after that 2 ft all RF is being blocked out or reduce to almost zero by the Choke. This just mean any ground wire After the Choke should only pass a DC current to ground which is good for lighting strikes.
If I went by the rules only very strictly, then my transmitter could only be mounted
around 2 feet off the ground. I have 2 transmitter made by different companies and they both use around an 8 ft antenna. That only leave me a 2 ft ground wire to my grounding rod.
This is why I called the FCC on this issue. I think this may be on some of the Manufactures websites of how to use a RF Choke in the ground system.
They may have been told this as well.
I always say when in doubt ask questions.
Well I have said enough and will let everyone get back to their talking.
I will now back out this conversation and let you all have it back
Thanks
June 15, 2019 at 2:19 pm #111567Below is a link to important information about why and how coaxial cables produce e-m radiation into space.
https://www.w8ji.com/common_mode_current.htm
June 15, 2019 at 2:46 pm #111572Thank you for sharing that, Sean. I’m sure all here agree that your comments are appreciated and welcome here anytime.
John
W9LWA
June 15, 2019 at 4:44 pm #111575Hi John
I know you are a Ham Radio operator. Rich keeps referring to W8JI
website but not sure if he is W8JI who has one of the largest ham Antenna
set ups in this country. I am a Ham operator and have been for 4 decades plus
some. I do hold an Extra Class license. Most my receivers and transmitter have been refurbished by me to get them back up on the air. Other I have design and built just to see what they could do. I love tube type radios and transmitters.
Anyways the only reason why I have not designed a part 15 transmitter for the market is that their enough of them on the market already and some are really well design and built.
There really is no reason just to add another one to the market. The transmitter
is really not the Issue. Since if anyone uses a class E type Biasing you will get around 100% output power of the DC input power. The problem is that You only get out as well as your antenna is design.
What have ham radio operators been saying for years. It not the power that gets you out it the Antenna.
So once you have the full 100mw output power then it come down to the Antenna design.
That a whole ball game in itself. And their so many variables that effect part 15 antenna systems. Biggest one is the limit of the 10 FT antenna if you use no feed line or ground connection.
My goal in the future is to introduce a part 15 antenna that has very little loss in the Matching section. I have all the correct test equipment to test antennas.
I did this for a living so I do know this area very well.
Anyways this thread is not about this but I wish you all the best in trying out the ISS extender antenna.
Set up correctly it should perform quite well.
Thanks
June 15, 2019 at 9:31 pm #111578Good post. Especially enjoy your comments regarding Part 15 technology. Are you aware if any of the current transmitters actually getting 100 mw output? I’d heard about the most was around 60 mw out, be that right or wrong. Agree about antennas. I think there’s room for something more efficient.
I’m waiting to hear results of what kind of range people will get with the ISS extended range set up. I was going to go with Rangemasters since those can be networked but I’m thinking if range on the ISS is something approaching a mile, I might not fool around with trying to network several transmitters.
In addition to communications law, my firm (www.seeslaw.com) has several locations here in Indiana where we only handle consumer bankruptcies. I’m thinking of setting up a transmitter at each location to play music and maybe a ten or fifteen second commercial for the firm every 15 minutes. I don’t know how cost effective that will be, but I suppose the costs will be tax-deductable even if it isn’t.
I guess we’ll see how those test results go to determine which kind of transmitters we’ll be deducting for…
John
W9LWA
June 23, 2019 at 7:10 pm #111690I’m assuming the RG6 braid attaches to the chassis at the transmitter end and the chassis at the range extender in the common fashion for coax through connecters. There isn’t any reason this would be different, is there?
I’ll admit I haven’t quite figured out how this got certified, but a local know-it-all (worse than me, even) is spinning a tale about complicated thing that involves the braid not being connected someplace…
I hope he doesn’t know something I don’t about this…
John
W9LWA
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