Aircraft scanning question

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mike619

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I was curious how I could hear an aircraft on a scanner say it is flying over you're house for example what should you tune to the tower,ARTCC,or approach/departure?
 

kma371

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I was curious how I could hear an aircraft on a scanner say it is flying over you're house for example what should you tune to the tower,ARTCC,or approach/departure?

Like others said, it depends on altitude, asending, decending, flight plan, direction etc.

If it's high level, Center controler or approach/departure
Low level, could be approach/departure or tower
Or they may not need to have any communication with anyone.

Close call works good with aircraft real close. Then you can tell what freq is used in your sector.
 

krazybob

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Another thing to put in your tool kid is whether or not the aircraft is flying East or north or west or south. That will give you an idea as to their intentions. Aircraft flying north and east fly at odd numbers plus 500 feet. Aircraft flying west or south fly at even numbers plus 500 feet. You're probably not going to be able to tell their altitude from ground level but remember that the sun rises in the East and sets in the west. That'll give you an idea of direction. If you know where the airport is at that'll give you a clue as to whether they're landing or taking off. If you're real close to the airport it's kind of obvious to see when it's climbing but not always. I remember before I got my license I used to lay by the swimming pool at my apartment building and San Gabriel Valley California and I was about 1 mile from the airport. I sit there and listen to him on the scanner by the time I became a student I was pretty good on the radio. But I could tell whether they were in the pattern downwind and a beam, turning base, on final. There's some good resources to Google that might help you. I looked this up for you and it'll give you a good insight. Otherwise just kick back and enjoy listening to the airplanes.

https://en.m.wikipedia.org/wiki/Airfield_traffic_pattern

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RTL1090 is pretty easy to set up and get going. http://rtl1090.com/

I run it on an ACER Netbook, on my XFRD630 Dell..it does not take up too much ram,or stress the CPU excesively.
it has a basic scope feature, it will populate the airspace in the area that you are in/your antenna can RX.

sonicgoose has a good how to..http://sonicgoose.com/tag/rtl1090/

I also pipe the data out to ADSBScope, it has a more detailed layout..But RTL1090 will get you going just fine..
http://www.sprut.de/electronic/pic/projekte/adsb/adsb_en.html

I run it off of a NooElec NESDRSmart...But any descent SDR stick will work...20-25 $ is a good cap on cost.
http://www.nooelec.com/store/nesdr-smartee-sdr.html?SID=6mfv4p5469ds2bbqbqdjc169k5

theres a mild learning curve to dial it in, but its not rocket science.

It also works mobile..I have an MDT set up in my truck...I run SDR#...ADSB..ect...well worth the time to learn.
 
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krazybob

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RTL1090 is pretty easy to set up and get going. http://rtl1090.com/

I run it on an ACER Netbook, on my XFRD630 Dell..it does not take up too much ram,or stress the CPU excesively.
it has a basic scope feature, it will populate the airspace in the area that you are in/your antenna can RX.

sonicgoose has a good how to..http://sonicgoose.com/tag/rtl1090/

I also pipe the data out to ADSBScope, it has a more detailed layout..But RTL1090 will get you going just fine..
http://www.sprut.de/electronic/pic/projekte/adsb/adsb_en.html

I run it off of a NooElec NESDRSmart...But any descent SDR stick will work...20-25 $ is a good cap on cost.
http://www.nooelec.com/store/nesdr-smartee-sdr.html?SID=6mfv4p5469ds2bbqbqdjc169k5

theres a mild learning curve to dial it in, but its not rocket science.

It also works mobile..I have an MDT set up in my truck...I run SDR#...ADSB..ect...well worth the time to learn.
Well then my scope would be quiet large. I live at 6300 feet above Southern California and I can hear aircraft for several hundred miles. With that said, what I can hear at 1 GHz is another story. That means I would be able to hear the aircraft communicating with the a station but not pick up its transponder.

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N9JCQ

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Mike619, I don't think I saw an accurate answer to your question. Theoretically, if you knew the traffic patterns over your location, then yes, you would enter in the approach/departure frequencies, regional air traffic control frequencies that are near/over you. Planes are not talking continuously so its "catch as catch can" but its certainly possible.

For example, https://www.airnav.com/airport/SAN will show most of the frequencies for San Diego Internationale. When you go to that page, note the Sectional chart to the right. Click on that and although it looks like a nightmare, you will see the various areas of control. Further down the page you will see the various approach and departure plates for that airport, complete with intersections and marker names.

Once you get used to the nomenclature and routing, its easy to figure out. I hope this helps.
 

krazybob

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I am looking at ADSB antennas and wonder if anyone has tried one of these? Looks like they come from China and have something stuffed into ABS plastic. Might work, might not. They quote it as 9dBi, which is about 6.8dBd but a 14 degree vertical beamwidth. They have a second model quoted as 6.5dBi, which is actually 4.3dBd but also with a 14 degree beamwidth. The lower gain should have a broader vertical beamwidth.

But has anyone tried one?

6.86dBd - https://tinyurl.com/yddwdmfb

4.36dBd - https://tinyurl.com/yddwdmfb
 

dlwtrunked

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I am looking at ADSB antennas and wonder if anyone has tried one of these? Looks like they come from China and have something stuffed into ABS plastic. Might work, might not. They quote it as 9dBi, which is about 6.8dBd but a 14 degree vertical beamwidth. They have a second model quoted as 6.5dBi, which is actually 4.3dBd but also with a 14 degree beamwidth. The lower gain should have a broader vertical beamwidth.

But has anyone tried one?

6.86dBd - https://tinyurl.com/yddwdmfb

4.36dBd - https://tinyurl.com/yddwdmfb

Keep in mind that the beamwidth is not sharp and has a shape to it. Your thinking might apply if that were not the case. And the same can be said about the gain. I assume you also considered the popular https://www.amazon.com/1090MHz-ADS-...pID=21bOpPKh5gL&preST=_SX300_QL70_&dpSrc=srch

And for many, an ADSB filter has a great effect.
 

krazybob

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Keep in mind that the beamwidth is not sharp and has a shape to it. Your thinking might apply if that were not the case. And the same can be said about the gain.
The higher the gain of an antenna the narrower the beam width. That's because the aperture is narrowed so that it focuses more on the horizon.

If you have a 20 guys blow me at the base of the mountain and I am using a discone antenna with 0dB gain they will hear me just fine. In fact for quite a distance.

Now then, if we narrow the aperture of the antenna so as to squeeze it off more towards the horizon that are round a bulb we get 6dBd we get more gain out at the horizon and less game directly below the antenna.

The same remains true if we narrow the aperture of an antenna so as to squeeze it off even more towards the horizon that offers are round 9dBd gain the people down below we're going to go, "Bob, who are you talking to?" And that particular case I station from Mammoth Lakes, California heard me because he had a clear path to me and I to him. To elevated stations have much greater range and High Gain antennas other situations.

The point is that the beamwidth should be greater with the Lesser antenna because it's pattern is not tightened towards the horizon. This is one reason I'm aware of that airport control Towers use antennas that can look nearly straight up. They look like discounts but they're meant for VHF only I guess. I don't know. I'd have to ask somebody that knows. But I can tell you that there's a multi Spike and 10 other chooses the path of least resistance and it works against the ground for gain.

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krazybob

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The higher the gain of an antenna the narrower the beam width. That's because the aperture is narrowed so that it focuses more on the horizon.

If you have a 20 guys blow me at the base of the mountain and I am using a discone antenna with 0dB gain they will hear me just fine. In fact for quite a distance.

Now then, if we narrow the aperture of the antenna so as to squeeze it off more towards the horizon that are round a bulb we get 6dBd we get more gain out at the horizon and less game directly below the antenna.

The same remains true if we narrow the aperture of an antenna so as to squeeze it off even more towards the horizon that offers are round 9dBd gain the people down below we're going to go, "Bob, who are you talking to?" And that particular case I station from Mammoth Lakes, California heard me because he had a clear path to me and I to him. To elevated stations have much greater range and High Gain antennas other situations.

The point is that the beamwidth should be greater with the Lesser antenna because it's pattern is not tightened towards the horizon. This is one reason I'm aware of that airport control Towers use antennas that can look nearly straight up. They look like discounts but they're meant for VHF only I guess. I don't know. I'd have to ask somebody that knows. But I can tell you that there's a multi Spike and 10 other chooses the path of least resistance and it works against the ground for gain.

Sent from my SM-N920V using Tapatalk
I checked out the antenna you pointed me to and it looks okay. The mounting brackets don't impress me much. I use professional mounting brackets to withstand hundred mile an hour winds. I got a whole box of them so I don't have to buy them. They're not cheap. At any rate, it looks like they expect you to use 75 ohm coax cable on these antennas and at that high-frequency you're going to have such a stream lost if you're basically going to be unusable. And a very very minimum I would be running lmr400 with a preamp on it. Otherwise it's my budget could afford it I would be using 7/8 or 1 and 1/2 in hard line.

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majoco

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Yes, that's ok to identify the aircraft, but he wants to listen to the to-and-fro conversations. I don't know where you can access them in the US but here I can download free the approach and departure charts for any airport in NZ and round the South Pacific islands. Across the top of the chart you can see all the low level frequencies for that particular approach - there will be another chart for departures with different frequencies.
 
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questnz

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Nov 18, 2009
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Thanks Martin will send you PM, I didnt know about the listening option on Flight Aware
Beside scanners I've got 2-3 older RTL dongles, 2 x RTL3 dongles intended to use the laptop on travels, setup for trunking, 1 x FlightAware Pro dongle and recently shipped SDRPlay RSP1A.
All SDR stuff is a new hobby thingy for me after scanning for 30+ years, very much still in learning stage. Got Omni-X on the roof feed via Antsig 4 way splitter amp and 5D-FD coax from Antenna. Hamilton Airport about 18 kms in the straight live, hearing good on small Uniden 355XLT desktop or 396XT handheld.

Regards Chris
 

majoco

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Chris, I hope I didn't mislead you, I know nothing about ADSB or Flight Aware - I thought the OP wanted to listen on a scanner to the aircraft overhead. If you can set up an RTL SDR to scan a variety of frequencies in the aircraft VHF band then that's the way to go, but I tried that on an early RTL stick and it was pretty useless if you wanted cover more than say five frequencies - my UBCT8 does nicely covering Palmerston North, all the Ohakea overhead, local and military, probably 20+ frequencies - Palmy Tower is a bit scratchy as he's over the hill from me.

(I said I know nothing about ADSB, that's not quite true, I was an AirNZ avionics engineer!)
 
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