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  • iamnothere
    replied
    feed_stats
    Screen Shot 2015-07-23 at 11.40.30 PM.jpg

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  • Rooster
    replied
    What is this "position report" ?

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  • abcd567
    replied
    Originally posted by iamnothere View Post
    @abcd567 I have a question , is it possible build a antenna limited in short range like 100nm , goal is more position report .

    Regard

    Griffin
    Originally posted by Rooster View Post
    Just use a known working antenna... and then limit the RF gain on the receiver (if you are using an RTL dongle etc)
    Otherwise fit an attenuator to the feeder.
    In addition to what rooster has rightly suggested:

    (1) Remove amplifier if there is one.

    (2) Use a low gain antenna such as ¼ wave whip with groundplane (Spider, Cantenna etc), instead of a high gain antenna (high gain commercial antenna or a good DIY CoCo).

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  • iamnothere
    replied
    Originally posted by Rooster View Post
    Just use a known working antenna... and then limit the RF gain on the receiver (if you are using an RTL dongle etc)
    Otherwise fit an attenuator to the feeder.
    Thanks replay , yes I am use RTL dongle .

    If reduce the RF gain could it influences position report ?

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  • Rooster
    replied
    Originally posted by iamnothere View Post
    @abcd567 I have a question , is it possible build a antenna limited in short range like 100nm , goal is more position report .

    Regard

    Griffin
    Just use a known working antenna... and then limit the RF gain on the receiver (if you are using an RTL dongle etc)
    Otherwise fit an attenuator to the feeder.

    Leave a comment:


  • iamnothere
    replied
    @abcd567 I have a question , is it possible build a antenna limited in short range like 100nm , goal is more position report .

    Regard

    Griffin

    Leave a comment:


  • abcd567
    replied
    Originally posted by AzKo View Post
    And spider is working. First time i see my radar in FR24

    [ATTACH=CONFIG]6267[/ATTACH]
    ONNEKSI OLKOON
    CONGRATULATIONS!

    Wow, you live near Rovaniemi Airport, which is at Arctic Cirle! I felt Toronto is very cold, but it is no comparison to your place!

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  • AzKo
    replied
    And spider is working. First time i see my radar in FR24

    nimetön.png

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  • abcd567
    replied
    Originally posted by rodeo View Post
    On a slight deviation from the topic, but semi-related .... :-)

    abcd567 - what are you using to generate the graphs in post #2402 ??

    Cheers.
    These curves are generated on Raspberry Pi, using "RRD Tools Collectd" - original work by @obj: (Oliver Jowett), and automated installation script by @Xforce30164:

    For the tool to work, in your RPi, you have to first replace dump1090 (Malcom Robson) with dump1090-mutability (Oliver Jowett), then install the "rrd tools "collectd", either directly (difficult) or using script by xforce30164 (easy).

    My DVB-T is connected to a Raspberry Pi. The RPi has Raspbian Wheezy Operating System, dump1090-mutability decoder/receiver, and FR24, Planefinder, and Flightaware data feeders installed. In addition I have installed "rd tools collectd".




    To make it easy for you, here is the code;

    (1) To install dump1090-mutability see the code here: DUMP1090-MUTABILITY (for advance users)


    (2) To install the "rrd tools collectd" using automated script by xforce30164:

    Code:
    cd ~
    sudo apt-get install rrdtool && sudo apt-get install collectd
    wget http://raspi.ayadex.com/volatile/web_install.sh
    sudo chmod +x web_install.sh
    sudo ./web_install.sh "dump-tools"
    cd dump-tools
    sudo ./install.sh "crontab"
    
    [COLOR="#FF0000"][B]# First attempt of  [I]sudo ./install.sh "crontab"[/I] may show failure. Repeat the command, and it will show crontab installed.[/B][/COLOR]
    
    sudo reboot

    To see the graphs:
    (1) In RPi browser - type in your browser http://localhost/collectd or http://127.0.0.1/collectd

    (2) In Desktop/Laptop browser on the same network type http://<ip address of RPi on local network>/collectd. The IP address of RPi can be found from router setup page and will be something like 192.68.2.15

    Please take care while typing "collectd". There is no e between t & d.


    For further details, please see these links:

    (1) dump1090 Collectd graphs and automated Installation script - by xforce30164

    (2) Flightaware Forum - System Monitoring

    (3) Planefinder Forum - Web Portal and Collectd/rrd graphs automated installation

    (4) RRD Tool - Original Author Tobi Oetiker - 1999

    (5) Collectd - Original Author Florian Forster - 2005
    Last edited by abcd567; 2015-07-22, 19:47.

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  • rodeo
    replied
    On a slight deviation from the topic, but semi-related .... :-)

    abcd567 - what are you using to generate the graphs in post #2402 ??

    Cheers.

    Leave a comment:


  • loplo
    replied
    Indeed, it's a maintenance vehicle -> http://ightwww.flightradar24.com/data/airplanes/mtc25/

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  • abcd567
    replied
    Look what I caught on my receiver:
    A Crazy Pilot Taxiing Under Influence of Alcohol?
    No it is an airport maintenance vehicle fitted with ADS-B transponder!


    Last edited by abcd567; 2015-07-22, 07:15.

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  • iamnothere
    replied
    Thanks , abcd567

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  • abcd567
    replied
    Originally posted by AzKo View Post
    Build spider today when finally get some stuff to build something. And im not also so good solder. But main thing is that antenna is working

    [ATTACH=CONFIG]6265[/ATTACH]
    Good work!

    Spider is one of the easiest and very reliable antenna for begginners. In fact all antennas with a ¼ wavelength (69mm) whip and a groundplane (metal disc, horizontal radials, slanting radials, or a food/drink can, also known as Cantenna) are ideal for beginners.

    The reasons are:

    (1) These antennas are naturally resonant, i.e. have an impedance close to 75 ohms, which matches with the Coaxial cable, Amplifier & Receiver (dvb-t) impedance and gives a swr less than 1.5, a highly desireable situation.

    (2) These antennas have high dimensional tolerance, so few mm error in length of whip or radials or few degrees error in bending down the radials does not appreciably degrade its performance.

    Dont worry about soldering. The antenna works good even if the soldering is not very good.

    Please click the link below to see 4 different antennas, all with ¼ wavelength whip, but each with different methods of providing groundplane.


    http://forum.flightradar24.com/threa...-FOR-BEGINNERS
    Last edited by abcd567; 2015-07-20, 23:38.

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  • AzKo
    replied
    Build spider today when finally get some stuff to build something. And im not also so good solder. But main thing is that antenna is working

    2015-07-20 22.39.17.jpg

    Leave a comment:

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