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  • #46
    i did not write something different. It also does not make sense to connect the stick to the Raspi and then unsing a rubbish coax cable.

    All single parts must habe a certain level of quality. The chain is always only as good as the weakest chain link

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    • #47
      Originally posted by magnum View Post
      It also does not make sense to connect the stick to the Raspi and then unsing a rubbish coax cable.
      I have extensively used both options (pigtail & usb cable). I never had any complaint about pigtail, but had several occurances of usb cable problem.

      Also I have never seen anybody complaining about pigtail. If there was any complaint, it was wrong or bad connector or adaptor. However in these forums, I have come across a large number of complaint arising due to bad usb cable.

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      • #48
        No harm in using a USB cable if you already have one. Most likely it will prove OK, and you will save cost of a pigtail (but you will still need to purchase an adaptor F-female to SMA-male). If the USB cable gives problem then either replace it by another good quality usb cable or a pigtail.

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        • #49
          if you clamp down the RG-6 coax, you can get away with having the cable not be flexible.

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          • #50
            Originally posted by wiedehopf View Post
            if you clamp down the RG-6 coax, you can get away with having the cable not be flexible.
            Good idea. In this case neither pigtail nor usb extension cable is required, only F-female to SMA-male adapter is needed (and an F twist-on male on the coax itself).

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            • #51
              After looking in my cable stash, I do not have any USB extensions, good or otherwise, or pigtails, so, clamping the RG6 it is. !!! But, another thought just occurred to me, using my Diamond D130J airscanner antenna which is extended above my rooftop now . The Flightaware prostick plus has a amp and 1090Mhz filter., and I remember wiedehopf replying in another thread, it could work ok.

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              • #52
                From Flightaware forums.
                Dated January 2015 (before Flightaware ProSticks existed)

                Originally posted by k6rtm
                Here is part of what will eventually be one of a number of web pages on ADS-B related topics.

                You may have run into one or more of my posts talking about filters. Why are they needed and what will they do? Let's look at some real world data.

                I have a discone antenna on the roof, with good feedline (9913) to my office downstairs. We have a good view of the Silicon Valley.

                When I connect the discone to my spectrum analyzer (a venerable HP8594E), here's what it sees:


                This is the spectrum from 50 MHz to 2.0 GHz, along the horizontal axis. The vertical axis is signal intensity, at 10 dB intervals. The numbered diamonds are frequencies of interest

                <1> is 1090 MHz, the frequency we're interested in. Any ADS-B signals are down in the weeds.
                <2> is 2451 MHz, a nearby 2.4 GHz Wi-Fi access point
                <3> is 884 MHz, a DTV station
                <4> is 748 MHz, another DTV station
                <5> (no diamond) is around 1900 MHz, a local cell site

                The spikes below <4> are other DTV stations, business band things, and the FM broadcast band.
                Those DTV stations are around 30dB stronger than any signal we want at 1090 MHz -- 30dB is a factor of 1000!
                From this it's clear that we have a LOT of signals that are hundreds to thousands of times stronger than the ADS-B ones we want. These strong signals are going to swamp our little SDR!

                Let's put a Mini Circuits SHP-1000 high pass filter between the antenna and the spectrum analyzer. Here's what we get:


                Pretty much everything below 750 MHz is gone. The spike at <4>, 748 MHz, has been cut by 25 dB -- a 320 times reduction. Our spike at <3>, 884 MHz, has been cut by 6 dB, which is pretty good.

                Note that our cell site at <5> is untouched -- this is a high pass filter after all.

                The addition of a high pass filter has cleaned up the signal we need to work with tremendously. This will be all a lot of sites need to improve ADS-B reception. Another advantage to adding a high pass filter is that the filter will provide some protection for the front end of the SDR.

                What about these incredible surface acoustic wave (SAW) filters? What do they do? Here's the frequency response of the EPCOS 1090 MHz SAW filter:


                This frequency sweep is from 50 MHz to 1200 MHz, not 2.9 GHz like the top two; the response from 1200 to 2900 MHz isn't that interesting.
                This SAW has a measured insertion loss of 4.72 dB at the center frequency, measured at 1089 MHz. The measured 3 dB bandwidth is about 26 MHz. Signals below 1100 MHz are attenuated by around 46 -- gone. (This plot was generated by a HP 85630A scalar test set which works with the HP8594E spectrum analyzer.)

                The combination I use -- a SHP-1000 high pass filter connected to the discone antenna. This filters out most of the garbage, and more important, has a very low insertion loss, so we're not attenuating the signals we're interested in by much. The output of the high pass filter goes to a low noise amplifier (LNA). The LNA is followed by a SAW -- and the LNA compensates for the insertion loss of the SAW. This provides a signal for the SDR to process that only has energy around 1090 MHz.

                And by the way, if you have a SDR, you have a spectrum analyzer -- you can find out just what your antenna is delivering, with and without a filter.

                --bob k6rtm

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                • #53
                  Thanks for this abc, Yeah, right.....sort of like reading a doctors rendition of his findings. So my limited understanding is that before the advent of filters, my discone would swamp the 1090Mhz signal I am looking for with other signals far more powerful. But, with the Prostick filter, I will have a better chance? Though, maybe my little spide to be built maybe better?
                  Last edited by POR911; 2019-10-12, 01:59. Reason: later thought

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                  • #54
                    POR911:

                    The signal path inside ProStick Plus (dark blue) is as follows:

                    RF in >> LNA >> SAW filter >> DVB-T

                    The LNA being before the filter, encounters the cell/mobile, TV, & FM signals picked by the antenna. In most locations these signals are quiet strong, and the LNA gets swamped/overloaded by these. In most locations, an external filter between ProStick and antenna is required to remove these signals so that these dont reach and swamp LNA.

                    The RadarBox24 FlightStick has filter chip before LNA, and generally dont require an external filter, except at very RF noisy locations.

                    RF in >> SAW filter >> LNA >> DVB-T

                    Anyway, dont worry now for the filter. Hookup your Diamond Discone to ProStick and see what you get.Once your system with Discone is up and running, you can conduct an RF scan very easily which will show what signals are arriving at the dongle.

                    Do I need a Filter? - Find RF Signals In Area
                    Last edited by abcd567; 2019-10-12, 03:37.

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                    • #55
                      ok, RW stuff out of the way, Looking at abc thread, .....How to Install dump1090-mutability_1.15~dev on RPi..(now not dev)

                      TO HAVE A TROUBLE FREE INSTALLATION, IT IS REQUIRED TO MAKE A FRESH INSTALL, AS SHOWN BELOW:
                      (a) Format microSD Card
                      ...done
                      (b) Write Raspbian Image....done Rasbian lite image...I assume now, I need to get the RPi working and connected to PC and net. Also, putty working, IP addresses sorted, then check for RPi updates etc, then reboot before (c)?

                      Then, can I copy and paste below (shift/ctl/c and shift/ctr/v)

                      ... sudo bash -c "$(wget -O - https://raw.githubusercontent.com/abcd567a/dump1090/master/install_dump1090_mut_1.15.sh)" from here to the RPi?

                      (c) Install dump1090-mutability (Steps 1 to 10).

                      Is the action above all I need to do before (d)

                      (d) Install data feeders FR24, Flightaware, & Planefinder (Steps 11, 12, & 13).

                      It is important that first dump1090-mutability is installed, and data feeders are installed after dump1090-mutability has been installed.

                      When I see code writen in multiple lines, for example below, is it carried out by entering line 1..wait until done, then line 2 etc, or copy/paste the lot together?
                      sudo apt-get update
                      sudo apt-get install lighttpd
                      sudo apt-get install dump1090-mutability
                      sudo lighty-enable-mod dump1090

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                      • #56
                        Originally posted by POR911 View Post
                        ... then reboot before (c)?
                        Not ncessarym but preferred

                        Originally posted by POR911 View Post
                        Then, can I copy and paste below (shift/ctl/c and shift/ctr/v)

                        ... sudo bash -c "$(wget -O - https://raw.githubusercontent.com/abcd567a/dump1090/master/install_dump1090_mut_1.15.sh)" from here to the RPi?
                        (1) Copy from web page: shift/ctl/c. Paste inside PuTY: Bring cursor (green rectabgle) to the point where you want to copy, then place mouse pointer anywhere on PuTTY and Right-Click the mouse.

                        STEPS 1 & 2 in screenshot below
                        How to Copy-Paste To or From PuTTY.png


                        (2) Avoid copying from a web page outside the code block as often URL are shortened in web page and fail in PuTTY
                        Copy only from inside a code block (see below).
                        Code:
                        sudo bash -c "$(wget -O - https://raw.githubusercontent.com/abcd567a/dump1090/master/install_dump1090_mut_1.15.sh)"

                        Originally posted by POR911 View Post
                        (c) Install dump1090-mutability (Steps 1 to 10).

                        Is the action above all I need to do before (d)
                        Do steps 10, 11 & 12 only after completing steps1 to 6 (7,8, & 9 are optional)

                        Originally posted by POR911 View Post
                        It is important that first dump1090-mutability is installed, and data feeders are installed after dump1090-mutability has been installed.
                        YES, VERY IMPORTANT, else FR24 feeder will create a mess


                        Originally posted by POR911 View Post
                        When I see code writen in multiple lines, for example below, is it carried out by entering line 1..wait until done, then line 2 etc, or copy/paste the lot together?
                        sudo apt-get update
                        sudo apt-get install lighttpd
                        sudo apt-get install dump1090-mutability
                        sudo lighty-enable-mod dump1090
                        ONE-BY-ONE


                        .
                        Last edited by abcd567; 2019-10-13, 06:34.

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                        • #57
                          When you first log into the RPi, and you get to the config screen, do I need to do anything here? I guess change the password, and maybe update tool to the latest version? and i suppose any other updates? I saw in advanced options, A1, Expand file system? Do I need more space? How do you quit the RPi...
                          Getting there.....

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                          • #58
                            Having more space doesn't hurt, expand away.

                            If you don't have SSH access already, you will want to enable it in that menu.
                            Maybe set your timezone?

                            I'm partial to the tools below because i maintain those install scripts and for some stuff like tar1090, i've done some extensive modifications on that:
                            https://forum.flightradar24.com/thre...1090-et-cetera

                            If you install dump1090-fa with one of my scripts, all that's needed is that you have setup fr24feed before.
                            If fr24feed isn't getting any data/planes, the install script for dump1090-fa will fix that and supply data.
                            The signup process where you get a share key and provide your mail address needs to be already completed though.

                            Have fun tinkering, are you receiving planes yet?

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                            • #59
                              Thanks Wiedehopf, Still at the boot...what does this mean and do phase. RW keeps rearing its head, so have to keep dropping by the office and tinker. When I created the image, I also created a SSH text entry in the boot area. Not sure why yet, but Its need will pop up eventually. I loaded the lite version, so its not big on assistance.
                              I noticed that when you plug in the Flightaware dongle, it leaves no room to use the other three USB. So it looks like I need a right angle USB and or a USB extension...a good one of course.
                              Last edited by POR911; 2019-10-13, 12:26.

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                              • #60
                                RW? What do you mean?

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