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Author Topic: KSYR (Syracuse, NY) Feed Status - June 2012  (Read 14176 times)

Offline KSYR-pjr

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KSYR (Syracuse, NY) Feed Status - June 2012
« on: June 25, 2012, 11:34:22 AM »
To the few who had been struggling to listen to the KSYR (Syracuse, NY) feed this past year, I have an update for you:

Back in 2010 I had moved the feed from my home to a fellow pilot's home that was closer to the airport.  While the feed quality went from good to excellent, allowing me to add ground and clearance frequencies, the reliability of the feed suffered tremendously.   

I have made the decision to pull the feed back to my home and will be working do to so over the next two weeks (June 2012).  This will require removing the antenna and the high quality coax cable I had affixed to the other home and then re-assemble it to my home.  Lots of ladder and roof work are required, so it won't be something that happens at the snap of a finger but I am committed to trying to bring back a feed that is both reliable and of good quality.

What this means:   

Once I get the feed back to my home, it will be airborne frequencies only:  Tower (only aircraft just departing or approaching), and both approach frequencies.   At that point reliability should again return to near 99.9% available, as it was back from 2005-2010.

The ground-based frequencies will go dark, but only temporarily.  I am in the process of locating an alternate location for the ground frequencies, one that is close enough to the airport to provide good quality reception.   My goal is to try to make this remote location more reliable and accessible than the one that was hosting the feed over the last two years.

My apologies for the last two years.  It really was frustrating not being able to have the control over its reliability I had worked so hard previously to obtain.



Offline InterpreDemon

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #1 on: June 25, 2012, 02:33:24 PM »
Peter, how far are you from the airport, and what type antenna are you using?

Offline KSYR-pjr

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #2 on: August 10, 2012, 12:19:14 PM »
Sorry for the delay in getting back to you -

The feed, when it was originally at my house, was about 9nm from the airport.   The feed is still currently at a home that is about 2nm from the airport.  

I am still working to pull the airborne frequencies back to my home (and the 9nm distance) but I may leave the ground-based frequencies at the current location.   Again, when I had it home it pulled in the airborne freqs very well.  It was the poor reception of the ground-based freqs that inspired me to try to move the feed closer.  Problem is, I lost control of quality when I did so.

I have on order now a second j-pole antenna and a low-loss Belden coax cable.  It will probably be another week before they arrive.

Offline InterpreDemon

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #3 on: August 10, 2012, 05:58:30 PM »
Got your private message. The good news is that the 11SM you are talking about depends primarily upon elevation and intervening terrain since getting planes on the ground from ten miles line of sight is not a problem, at least not a problem as relates to affordable, available technology. I glanced at the frequencies involved and a custom 4 element, 10db yagi would do it for you depending upon whether that one APP channel up around 134 is transmitting from the field or not, and even if so that yagi could be broad-banded at a loss of about 2db and still probably do the trick. . . again assuming line of sight or close to it, say, skimming the treetops.

I am in the process of setting up a back-up feed for JFK from a distance of 8 SM with a broad-banded version of the 4-el yagi running at 45 feet AGL and delivering between 7 and 8.5 db from 121 to 130, and our preliminary testing is pulling in just about all the stuff on the ground including some walkie-talkies and tugs as well as planes sitting at the gates in and around all those terminal buildings, the toughest stuff being at the far side of the field (and buildings) and an additional mile away. Even a broad-banded omni-directional sleeve antenna ten feet above it (about 2db gain over a ordinary ground plane and on its worst day equivalent to a perfectly configured j-pole) was getting about 90% of the ground traffic, but the yagi filled in the gaps and made things solid. And that's with 4+ db loss in the 100' rg-58 cable run and no amplification (yet). But that path is at tree-top level so your results may vary.

The path analysis is the key because it may not be feasible to get a six-foot yagi above the trees whereas getting a sleeve dipole or your j-pole might be. On the other hand if above the trees is not possible in any event or there is intervening terrain the only way you are going to pull it out is with a strong array. As a rough rule of thumb you gain 3db for each doubling of elevation once you clear the trees, meaning it is not going to get you anything additional once you get that lightning rod above the squirrels, so the first thing you have to decide is if you can go that high. If trees are not an issue anyway because you live in the clear, than it is a no-brainer to go with a yagi as the only difference in signal that any additional elevation above roof-top will get you will be less noise from the blender in your kitchen, and that's only if your feed line is properly de-coupled.

One thing I can assure you... if you stick that j-pole at roof-top level and ground signals break squelch or can be heard to any degree at all within the noise, you will be able to pull them up to usable levels with a reasonable effort.

If you are handy and want to build your own antennas as I do all of mine, I'll be happy to model the dimensions for you once the requirements are known. I'll send you a photo of the JFK stuff. So get out your sectional and topo maps as well as Google Earth and get to work!

I just want you to know, Striker, we're all counting on you.

Offline KSYR-pjr

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #4 on: August 15, 2012, 12:07:27 PM »
LOL, love the "Airplane" reference.

Very good information.  Thank you for taking the time to post it.   I do have concerns on a couple of points:  Pretty sure I don't have an unobstructed line of site to the ground-based aircraft.  There is at least one ridge in between my home and the airport that probably places trees in between my antenna and those ground-based aircraft.  This is certainly what impacted the original feed (back when it was at my house pre-2010) and its ability to pull in most ground aircraft.   

The other concern is that I live in a neighborhood that would probably stab pins into effigies of me if I place a six-foot diameter yagi antenna well above my home.  Unfortunately I have to balance being a LiveATC volunteer with being a good neighbor.   The reality is that even on its best day the SYR feed would only pull in 12 or so listeners, so there is a high effort/cost to listener ratio.  This fact is what keeps me from going all out.


Offline InterpreDemon

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #5 on: August 15, 2012, 05:58:31 PM »
Well, if you don't have line of sight the elevation will do little good unless you are surrounded by trees, in which case the neighbors would not see your antenna anyway. That is why I recommend putting your new j-pole at roof-top level and seeing where we are. If you can hear anything on the ground even if buried in the noise and unintelligible, there is a good likelihood that 10db gain from a good yagi and perhaps some clean amplification will pull it out. Mid-band VHF like this has the ability to penetrate foliage... not as good as low-band (50Mhz) but better than high band (150 & up), so you can get some signal through penetration and scatter. You also may get a good bounce from a water tower, not unlike the "picket fence" bounce you get from overhead aircraft that occasionally allows you to hear things on the ground, which is why you need to assess the path.

The path for my feed is ten miles and far from line of sight, and as the trees on my lot are 75-100' up there is no way I would want to stick a lightning attractor way up there, hence my 3-element vertical yagi (for ATC voice) and 2-element horizontal (for the HPN ATIS on the CMK VOR located at the same site) are only about 25' up with the top of the tower occupied by other things. I combined both on one boom. You can see the pictures and the feed description here:

http://www.liveatc.net/forums/feed-setup-pictures/from-my-junkyard-to-your-ears/

Note that the 4-element I recommend for you would have almost double the gain as my antenna, and that one pulled modulation barely detectable in noise up to full copy, the only other advantage being that I use a real NAV/COMM radio instead of a scanner, but the advantage there has more to do with audio quality, squelch action and AGC than overall gain.

You should have gotten the photo I sent you of the 4-element for JFK, but basically the yagi looks like a conventional TV antenna turned on its side and with fewer elements, it has no "diameter", so it is doubtful you would get complaints, especially if it is just ten feet above the roof or strapped to a mast on your chimney.

Offline KSYR-pjr

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #6 on: August 28, 2012, 05:49:31 PM »
Thanks again for your recommendations and knowledge.   I will definitely explore that option for the antenna as an upgrade.  I fell back to a j-pole simply because that is what I had been using from 2005 until I moved the feed in 2010.  I just wanted to get the feed back up and under my complete control.   But now that it is up again and without the open squelch that had been plaguing it for the previous month or two I will look for ways to upgrade it.   I did get your picture and have saved it to revisit when I have time.

When you have a moment take a listen to the KSYR feed to see what you think - it is now up and running from my home and enabled here on the site.   Since bringing up the feed this past Sunday I notice there are good days and bad days with it.   Perhaps this is atmospheric or weather related?   Today is a good day and the feed sounds pretty strong.  
« Last Edit: August 28, 2012, 05:54:17 PM by KSYR-pjr »

Offline KSYR-pjr

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #7 on: August 29, 2012, 09:28:06 AM »
KSYR Update (Wednesday, Aug 29, 2012):

The airborne side of the KSYR feed is back under my complete control and is active.  

However, today the problem of the scanner's ability to squelch the stations has resurfaced.  There is either no squelch or it is VERY slow to engage.   Evidence to me suggests this issue is being caused by a recent defect with the scanner (a Uniden BC898T that is about 4 or 5 years old). I will be swapping the scanner either today or tomorrow when the replacement arrives.

Apologies for this continued and lingering issue that has plagued the feed for the last few months.  I will provide an update here when the replacement is in place.

Also, for the time being there will be no KSYR ground or clearance feed.  I am seeking out a suitable hosting location as well as considering antenna changes as recommended in this thread above.  Work and other commitments are taking priority right now, though, and prevent an immediate resolution to this.

Offline KSYR-pjr

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Re: KSYR (Syracuse, NY) Feed Status - June 2012
« Reply #8 on: August 29, 2012, 07:52:39 PM »
KSYR Update (Wednesday Evening, Aug 29, 2012):

The scanner with the apparent squelch problem has been voted off the island and replaced.  An FM filter was also added to the antenna line.  With these two changes the feed quality has improved quite a bit.  Thanks to Dave of LiveATC for his patience while we work through all of these hiccups in returning the feed to the quality it once experienced.

One notable issue remains:  The audio level, despite all involved audio adjustments being maxed out, is much lower than it should comfortably be.  This is a result of a cheap motherboard-integrated audio card in the laptop computer hosting the feed.  I have access to a USB audio dongle that I will be retrieving from another host site over the next day or two.    I am hopeful that this audio device, once installed, will give me better control over the audio level.

As soon as I have an update on this issue I will post here.