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Post by sparepart on May 25, 2019 15:07:33 GMT
"We will be shipping your Range Extender 2.5 in about a week" Scheduled (OK borrowed) the bucket truck to mount the ATU and Antenna on the pole the weekend of the 15th. Site is 45 feet ASL, pole adds another 20 feet to that. Plan is to use RG-11 coax between the Talking house and ATU.
Anyone want to help with the distance / field strength measurements?
SP
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w9lwa
New Member
Posts: 43
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Post by w9lwa on May 26, 2019 2:57:50 GMT
Well, I suppose I'm too far away to be any help with the testing, but good luck with the new installation. I hope it exceeds all expectations.
John W9LWA
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Post by sparepart on May 26, 2019 3:43:12 GMT
John, Will keep everyone posted on the outcome.
SP
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Post by thelegacy on May 28, 2019 1:06:02 GMT
I'm excited to find out your range too. You should check with a car Radio, strong Radio like a Tecsun or Sangean PR-D5 boombox Radio and also get yourself the Terk AM Advantage in case you have range issues. This way you can demo the loop in public and on Video for your town.
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w9lwa
New Member
Posts: 43
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Post by w9lwa on May 28, 2019 4:04:32 GMT
Well, I'm excited to see what the range will be, although I'll admit I don't know much about how the TH compares with other transmitters in other catagories such as sound quality and that sort of thing. There are more things to consider, but when dealing with such low power, range is a big thing.
I do have to wonder where this is all leading. If we have certification of a transmitter with a remote ATU and the intervening 25 feet of coax is considered "just inter-stage coupling between an exciter and final stage," as stated (correctly, IMO) by the Admin here on another thread, I suppose the sky is the limit, so to speak. So, why not spread out the transmitter circuits with inter-stage couplings so the transmitter is 100 feet tall (or whatever) and has less than a foot of actual antenna lead at the top and a foot of ground lead on the bottom?
Sometimes you just have to think big...
John W9LWA Does anyone remember that guy who used to sell ground wire tuners at hamfests? I used to see him everyplace, but not for a while. Something about reducing resistance, impedance and probably whatever else he could think of while making his pitch. I think it was really just half of an antenna tuner circuit.
If we can have an AT at the top of the tower, why not a ground wire tuner at the bottom? Problems with short antenna and ground leads solved?
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Post by thelegacy on May 29, 2019 4:20:35 GMT
My broadcast engineer friend tried this and it did make some difference.
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Post by sparepart on May 29, 2019 13:47:49 GMT
I recall seeing this - They are also called an artificial ground. From what I understand, they change the impedance (Z) and as a by-product can cause the ground lead to radiate.
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Rich
Full Member
RF Systems Engr (retired)
Posts: 112
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Post by Rich on May 29, 2019 20:51:50 GMT
...They are also called an artificial ground. From what I understand, they change the impedance (Z) and as a by-product can cause the ground lead to radiate. Just to note that all conductors of any impedance that are exposed above the surface of the earth and also carry r-f current will produce e-m radiation into space.
The greater that current and the longer that conducting path (other things equal), the greater will be those radiated fields.
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w9lwa
New Member
Posts: 43
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Post by w9lwa on May 29, 2019 20:56:26 GMT
I recall seeing this - They are also called an artificial ground. From what I understand, they change the impedance (Z) and as a by-product can cause the ground lead to radiate.
Indeed, the one I'm thinking of was probably about the same thing as the MFJ artificial ground unit. I suppose the question is where in the ground wire the AG would need to go. I talked to an "expert" at one of those places on line that sells MFJ stuff but he seemed unaware that a ground wire can radiate. I believe he finally told me that the wire coming out of the AG wouldn't radiate, but I don't think he thought the ground into the AG from the transmitter would radiate to begin with. I'll figure this out, but probably not from talking to him... John W9LWA Well, apparently MFJ says this AG unit needs to be connected to the transmitter or AT with as short a wire as possible. I don't know that I'm barking up the right tree with this thing, but at least I'm still barking...
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Post by sparepart on Jun 10, 2019 0:50:39 GMT
Working out the plan to test the Talking House and external antenna tuner. Plan is to set up Audacity to generate a repeating 30 second, two tone marker ( 850 Hz and 2200 Hz ), followed by a 15 second voice announcement. Plotted points on a street map at: 1/10 of a mile, 1/4 of a mile, 1/2 of a mile , and 1 mile. Have 6 of the cardinal and inter-cardinal compass points covered Will be using the stock Delco receiver in my truck as the test receiver. Any suggestions on how to improve accuracy?
BTW, Due to the alignment of the roads, some of the measure points are at different directions from the TX site.
SP
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Post by thelegacy on Jun 10, 2019 17:23:00 GMT
sparepart: Since you are doing a two tone and then an announcement you should be able to put up a video on youtube. I'd mount your cell phone on your back seat to the passenger headrest using bungee cord or maybe use a selfie stick but have the stick put inside the back pouch of the back seat to hold it up. This way you can drive and record without distracting or impaired driving. We should be able to hear the Radio and Youtube should not block you for any copyright issues.
Mention your distance according to the trip meter so we can hear what is going on.
Mounting your antenna as High as possible will certainly give better range results. Using a 20 Ft pole or putting your antenna 20 feet from the peak of the pitch of the roof should give great results according to what I've read in the manual.
And for the ones who own apartment buildings what a great idea install the ATU at the top of the building. As we saw with the rangemaster on top of a church steeple this should do relatively the same.
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Post by sparepart on Jun 10, 2019 22:25:32 GMT
sparepart: Since you are doing a two tone and then an announcement you should be able to put up a video on youtube. I'd mount your cell phone on your back seat to the passenger headrest using bungee cord or maybe use a selfie stick but have the stick put inside the back pouch of the back seat to hold it up. This way you can drive and record without distracting or impaired driving. We should be able to hear the Radio and Youtube should not block you for any copyright issues. Mounting your antenna as High as possible will certainly give better range results. Using a 20 Ft pole or putting your antenna 20 feet from the peak of the pitch of the roof should give great results according to what I've read in the manual. Underlying reason for tone and voice. YouTube can't lodge a copyright strike against a beeping noise.
Site is 45 feet ASL, the utility pole adds another 20 feet to that. Plan is to use RG-11 coax between the Talking house and ATU.
Would like to get readings in microvolts, however this will have to do....
SP
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Post by sparepart on Jun 14, 2019 10:40:39 GMT
UPDATE: Got a phone call my "borrowed" bucket truck will be on a paying job this weekend, so no antenna install.
Will keep everyone posted as renting one is out the question due to cost.
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