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  • Originally posted by peterhr View Post
    Could you also add a neon bulb across the output to and make it into a lightening discharge device?
    - would it work?
    Good Idea if it works. Since I lost 2 dongles to date due to lightening storms. None actually hit my antenna just close. I think the static in the air took them out. Now I unplug the dongles in heavy storms. Seems to work hahahah

    Andy
    Andy T-KTIK1

    RPI - http://Temporarily off Line due to t...98.37.214:8080

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    • Originally posted by andyk1 View Post
      Good Idea if it works. Since I lost 2 dongles to date due to lightening storms. None actually hit my antenna just close. I think the static in the air took them out. Now I unplug the dongles in heavy storms. Seems to work hahahah

      Andy
      Maybe a Zener Diod (breakdown voltage around 10 volts) is a better solution than neon (breakdown voltage 60 to 80 volts) for STATIC

      Above idea is just a brain wave. Needs investigation & study. Comments are most welcomed.

      Comment


      • Originally posted by andyk1 View Post
        Good Idea if it works. Since I lost 2 dongles to date due to lightening storms. None actually hit my antenna just close. I think the static in the air took them out. Now I unplug the dongles in heavy storms. Seems to work hahahah

        Andy
        Another brain wave:Storms induce static and surges on overhead power lines. These static and surges reach all equipment using power. Your Dongles most probably got damaged by surge & static on Power Line, rather than on your Antenna. Surge protected power supplies are commonly available in market at reasonable & affordable price.

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        • Originally posted by abcd567 View Post
          Another brain wave:Storms induce static and surges on overhead power lines. These static and surges reach all equipment using power. Your Dongles most probably got damaged by surge & static on Power Line, rather than on your Antenna. Surge protected power supplies are commonly available in market at reasonable & affordable price.
          Was a something I thought about. Since Computers, Beaglebone and Rpi's are all connected through a UPS/Surge suppressor I don't think that was the problem. Computers and all the rest never failed or UPS tripped. Well sometimes the do. My best guess is the strong static in the air those nights. Lightening does get close... maybe 100 yards/meters approx. from my home and antenna. None has ever hit (thank god) but house next door (a bit taller than mine) gets hit all the time. I don't understand that because my 1090mhz antenna is the tallest point for miles. approx. 45 feet/ 15 meters. I do have the antenna poll grounded and coax cable also statically grounded. Maybe the strikes are just to close. Have never lost any other electronics plugged through the UPS's and surge suppressors. I was thinking the NOO electronics Dongles had some sort of lightening protection (Static) but I guess not.
          Andy T-KTIK1

          RPI - http://Temporarily off Line due to t...98.37.214:8080

          Comment


          • I'd go for earthing the antenna, downlead outer and the negative of the Pi power, and possibly some sort of protection in case the downlead inner got a significant voltage difference from the outer.

            At least you only lost the dongle, HermanZA lost the Ethernet port on his Pi due to an electric storm - the Pi sacrificing itself to protect the dongle?

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            • PeterHR - LOL! I think my Pi was more selfish than anything else. But have to say, running it from Ubuntu feels more stable and reliable, tho the power consumption is way higher.

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              • Originally posted by peterhr View Post
                .........At least you only lost the dongle, HermanZA lost the Ethernet port on his Pi due to an electric storm - the Pi sacrificing itself to protect the dongle?
                I sometimes felt frustrated that I cannot install an antenna on roof of my building, eliminating the obstruction caused by surrounding building. But now I feel lucky to have strictly indoor installation: no lightning or static problem, no climbing up the tower or roof in -35C temperature, no antenna falling due to strong winds

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                • You don't have a neighbor on the other side of the building, that can host a similar system like yours for you ?

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                  • Originally posted by HermanZA View Post
                    You don't have a neighbor on the other side of the building, that can host a similar system like yours for you ?
                    Good idea, but unfortunately I dont have annyone friendly enough to host another system for me on other side of my building.

                    .
                    Last edited by abcd567; 2014-03-14, 19:34.

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                    • Originally posted by abcd567 View Post
                      ...But now I feel lucky to have strictly indoor installation: no lightning or static problem, no climbing up the tower or roof in -35C temperature, no antenna falling due to strong winds
                      I agree. At 1090MHz the average wood "stick" roof makes a very good radome since it's almost transparent to high UHF frequencies. And the broad structure of a house beats a rickety tower most times.

                      But there's still a risk from lightning! The same RF transparency means that the electromagnetic fields from a nearby lightning strike can induce currents into any conductor, including your antenna downlead, even indoors.

                      Using rough figures, a lightning stroke of 100MV traveling 10km to ground has a voltage differential of 10kV per meter. That's more than enough to induce damaging voltages into relatively short runs of coax cable. Don't think that you're 100% safe just because you're indoors. It's a lot safer, but there's still the potential for damage.

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                      • Originally posted by peterhr View Post
                        I'd go for earthing the antenna, downlead outer and the negative of the Pi power, and possibly some sort of protection in case the downlead inner got a significant voltage difference from the outer.

                        At least you only lost the dongle, HermanZA lost the Ethernet port on his Pi due to an electric storm - the Pi sacrificing itself to protect the dongle?
                        I missed that. Didn't know he lost it. Can he still access it to work using a usb wifi dongle? What I'm using. a cheap $10 B-Link from amazon.com. Works great.

                        Both my Antenna Poll and Cable are earth grounded using an 8 foot copper rod from home depot.
                        Andy T-KTIK1

                        RPI - http://Temporarily off Line due to t...98.37.214:8080

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                        • The dongle is plugged into an old PC running Ubuntu 12.04

                          Sent from my Nexus 4 using Tapatalk

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                          • Originally posted by Speed Daemon View Post
                            I agree. At 1090MHz the average wood "stick" roof makes a very good radome since it's almost transparent to high UHF frequencies. And the broad structure of a house beats a rickety tower most times......
                            Few centuries ago two New discoveries of those times were not easily accepted as they contradicted common observation & belief:

                            (1) The earth is round like a sphere.....come on, I look all around, and see it all flat..if it was round like a ball, person on its lower part will be upside down and fall...this new theory "earth is round" is nonsense.

                            (2) The earth revolves around the sun....come on, every day I see that the sun rises from east moves all day till it reaches west, and then goes beneath earth in evening, travels below earth all night and reach east to rise again from east next morning...this new theory that "sun does not revolve around earth, and earth revolves around sun" is all nonsense.

                            Current equivalent to above situation is that most ADS-B hobbyist find it hard to swallow following two facts:

                            (1) Microwave/UHF including 1090 MHz have very little penetration loss when they pass through building materials. As a result houses & small buildings (particularly areas near outer wall) are almost transparent to these frequencies. Hence taking antenna from indoors to outdoors does not appreciably increase signal strength.

                            (2) ADS-B Receiving Antenna's height has negligible effect on range as it cannot be physically put higher than say 100 feet due to cost of tower. Even at 100 ft height, the contribution of receiving antenna to the range is only 1.4x√100=14 miles (22kms), whereas the contribution of a plane flying at 10,000 feet is 1.4x√10,000= 140 miles (220kms), and contribution of a plane flying at 30,000 feet is 1.4x√30,000 = 243 miles (390kms). Therefore the main factors which decides range is the Aircraft height. With civil aircrafts not flying above flight level 400 (i.e. 40,000 feet), the range is limited to about 1.4x√40,000 = 280 miles (448kms).

                            Wait....If this was true, why I wanted to put my antenna on roof of my building?
                            Well my problem was that my building is surrounded by several tall buildings, which block the ADS-B signal to reach my antenna.
                            This "shadowing" effect could be overcome in one of the following two ways:

                            (1) My Building Management allows me to install my antenna on building roof, making it higher than other surrounding buildings, removing their shadow effect. Sigh! They did not allow .

                            (2) Owners of all surrounding tall buildings demolish their buildings and use the land to make a big Soccer field & Park...What a wishful thinking/day dreaming .
                            Last edited by abcd567; 2014-03-16, 07:37.

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                            • I have been using my Desktop & Laptop to feed data to FlightRadar24, RadarBox24 (AirNav Systems) & PlaneFinder.
                              The feed was "ON" only when I used my Desktop/Laptop, and off when I finished my work on computer & shut it down.
                              I am now considering using Raspberry Pi to provide uninterrupted feed.
                              Can anyone advise me the list of items I need to purchase?
                              I also have invitation to feed data to FlightAware.com, but it requires installation of PlanePlotter. Can PlanePlotter be installed on RPi? I want to use Ubuntu on Rpi
                              Last edited by abcd567; 2014-03-16, 07:22.

                              Comment


                              • Originally posted by abcd567 View Post
                                Current equivalent to above situation is that most ADS-B hobbyist find it hard to swallow following two facts:

                                (1) Microwave/UHF including 1090 MHz have very little penetration loss when they pass through building materials. As a result houses & small buildings (particularly areas near outer wall) are almost transparent to these frequencies. Hence taking antenna from indoors to outdoors does not appreciably increase signal strength.

                                (2) ADS-B Receiving Antenna's height has negligible effect on range as it cannot be physically put higher than say 100 feet due to cost of tower. Even at 100 ft height, the contribution of receiving antenna to the range is only 1.4x√100=14 miles (22kms), whereas the contribution of a plane flying at 10,000 feet is 1.4x√10,000= 140 miles (220kms), and contribution of a plane flying at 30,000 feet is 1.4x√30,000 = 243 miles (390kms). Therefore the main factors which decides range is the Aircraft height. With civil aircrafts not flying above flight level 400 (i.e. 40,000 feet), the range is limited to about 1.4x√40,000 = 280 miles (448kms).
                                I'd dispute those:
                                (1) when doing my initial set-up with the dongle and supplied antenna - I'd get maybe 50 miles range with it on the window board inside the window - opening the window, putting it on the cill outside, and closing the window on the wire increased range by about 50%.
                                (2) raising the antenna has a huge influence mainly due to getting it above local stuff that blocks the signal and possibly in eliminating some local reflections

                                For feeding FR24, I'm sure someone said they ignore position reports that are from over 400km away from your declared position - since they're probably in error.


                                Originally posted by abcd567 View Post
                                I have been using my Desktop & Laptop to feed data to FlightRadar24, RadarBox24 (AirNav Systems) & PlaneFinder.
                                The feed was "ON" only when I used my Desktop/Laptop, and off when I finished my work on computer & shut it down.
                                I am now considering using Raspberry Pi to provide uninterrupted feed.
                                Can anyone advise me the list of items I need to purchase?
                                I also have invitation to feed data to FlightAware.com, but it requires installation of PlanePlotter. Can PlanePlotter be installed on RPi? I want to use Ubuntu on Rpi
                                Raspberry pi might not be ideal, I believe Plane Plotter requires windows - FlightAware do have a Pi feeder for use on their own box - but last time I looked, they'd not released it as a separate software item. Maybe you'd be better off with an atom based single board computer or windows netbook.

                                back to the original question:
                                * Raspberry pi model B
                                * Case for the same (this is really to protect the SD card slot since side pressure on the card can easily damage the slot and the SC card won't press against the spring contacts)
                                * 5v 2A power supply with micro USB connector (you may have an blackberry / andriod phone charger that will work)
                                * some 4Gb (or more) SD cards (one for use, others to try alternate configs)
                                * It's helpful to have USB keyboard & mouse and an HDMI cable to connect to monitor or TV.
                                * Some method to write images to SD card - does your PC have an SD card slot?

                                Mostly for this - you'll run as light a weight debian as you can - the richer flavours like ubuntu may have drivers built in to drive the dongle as a TV receiver, which you have to disable to get rtl1090 / dump1090 to work. most of this is done on the command line - see the first few posts in http://forum.flightradar24.com/threa...e-to-feed-FR24 (probably best to continue this conversation there)
                                Last edited by peterhr; 2014-03-16, 08:16.

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