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W7PP

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Posts posted by W7PP

  1. Darren: Just looked at episode 1614 :wub: .... What a nice way to answer the question I asked on this topic. I haven't tried it yet, but can you change the startup config of dump1090 while using your infusion, or are we stuck with the "default" settings? You really don't need to have yet another episode to let me know the answer.... just reply here :rolleyes: ... Thanks again for the episode! (1614).... :grin:

  2. What are you talking about? SSh into the pineapple and run the commands just like you would on a laptop.

    Look at the "Config" screen of the infusion... I don't see any way to add, change or edit the way that dump1090 runs... Did I miss something? I would like to have something like "--quiet --net-bo-port 31012 and so on.... (not sure I got the syntax correct in my example....but) I want to listen to the output on a windows machine running VirtualRadar Server over wifi....

  3. :grin:

    Got my Pineapple today... took longer to install firmware than to get the tracker up and running... Question... how can I make changes to this infusion? If it's not open, then I have some suggestions... (1), Remember the map settings when leaving the “Map View”... (2) Allow use of the command line to start up dump1090 (maybe in the “Configuration” tab)...and.... (3) A setup page for the streaming of “beast” data to the outside world via a port on the Pineapple. OH and one more thing.... update the List view page every (x) as listed in the Config tab....

    :smile: Thanks, W7PP

  4. "Maybe it was multi-path interference off the blades. :D" Maybe it was the several MWatts of RF floatting around on the tower behind them, plus the one at the other end of the parking lot! On that tower behind them you will find everything from VHF to 22GHZ , and at ERP levels exceeding safe exposure limits !!! Move closer to that tower and warm up your lunch! :ohmy:

  5. Really interested in this! I have been setting up a BBB with an R820T SDR dongle to do this, but having problems with the wifi not always starting up. It (BBB) runs fine once I can get an IP and the wifi running... I can use the data to run VRS on my desktop W7 machine... until I figure out the wifi startup problem, I would like to see if the Pineapple/RTL would be more solid... I'll keep watching... This is what I use in Dump1090 now... works great !

    ./dump1090 --interactive --net --net-beast --net-ro-port 31001 --net-ro-size 500 --net-ro-rate 5 &
  6. Can I port the dump1090 data to another program (Virtual Radar) runing in the house on my windows machine? VR is a great program, Ive been using it with an antenna at 50 ft on my Ham Radio tower.... I get plots from 100-140 miles away, but I think I'm in trouble with the 100+ feet of coax from the tower top to the rtl dongle in the house.... I would love to move a pineapple and dongle up there and wifi the signals back to the house.... Can do???? :mellow: BUMP? Another bump.... hello, anyone alive here?

  7. """I doubt the RTL is 50 Ohm it's more likely to be a 75Ohm device as it's a TV receiver""" Yes it receives TV signals, but the hardware that attaches it to the antenna...ie. the MCX connector, is 50 ohms.... Along with that, I have seen many extra, made for ASD-B, preamps, antennas etc, that are almost always produced using 50 ohm connectors.... Some of these include... "N" connectors, SMA, RG316 coax... If your only clue to 75 ohm is that they are used to receive "TV" signals, then the overwhelming use of 50 ohm connectors should indicate that they are indeed 50 ohm devices....Every 75 ohm device I've seen on the net is prodced by hobbist... Just saying... :rolleyes: ! Oh, and by the way, 2% of a half wave using 82% VF coax is about 2 1/4mm. Remember when you change the elements for down tilt, you change the SWR.... It's a balancing act.

    Note on "N" connectors... I list them as 50 ohm because the only place on earth you will find the 75ohm "N" is in the cable TV business. They need to maintain low loss without impedance bumps along their lines and connections. B)

  8. Standard MCX connectors are 50 ohm.... SMA connectors are 50 ohm.... You can get 75 ohm MCX connectors but they are 10-15% more expensive as they are not "common" for RF use....

    also..... most of the small jumpers from MCX to SMA...even the "F" are made with RG316 cable... which is also 50 ohm.... Why does everyone use 75 ohm cable to make antennas for 50 ohm radios (DVB-T Dongles) ?

  9. My mistake.

    Of course,being a device intented for dtt reception,cable impedance is 75 Ohms.

    So You must use Rg-59.

    You can buy in every Ham-Shop (if they still exists!)

    ;)

    Standard MCX connectors are 50 ohm.... SMA connectors are 50 ohm.... You can get 75 ohm MCX connectors but they are 10-15% more expensive as they are not "common" for RF use....

  10. I'm referring to these sticks.

    Way, WAY smaller than the regular sticks and from the looks of it cheaper to boot but with identical specs.

    I'm considering getting one, but if anybody already has experience with one of these, I'm all ears.

    I have one of those.... works as good or better than the NooElec R820T (NESDR Mini)... The only thing I have found is they get a lot hotter when ran 24/7...

  11. I would have used something like a J pole antenna so that way you get a lower take off angle.

    There are plans online that mirror the Arrow Antennas J pole. It would IMO be eaiser to build and perform better than the colliner. The PVC had to effect the resonence of the antenna.

    The "J POLE" is a neat antenna... easy to make and it is grounded to help with lightining... but, it's no match for the gain you can get from a properly built collinear... The PVC you want to stay away from is... the gray or black types.... to many metals used in making them... White PVC pipe will only affect your antenna in the slightest.... Fiberglass is your best friend.... nearly zero affect...

  12. First off.... the idea of having 16 elements is for gain... The gain is produced by a couple of things. First is the amount of area of the entire antenna. If you look at it simply as 16 elements have twice the area as 8 elements.... second, the 16 element antenna has it's gain at a lower angle... lower to the horizon. If you want downward beam tilt... if your using a collinear on a high tower to talk to mobiles on the ground, you want the angle of the horizontal beam to be lower than the horizon.... With aircraft, they don't do so well at low altitude :rolleyes: ... so our ADS-B antennas do just fine with up-tilt... To get that tilt angle in the beam, to lower it, make the elements 2% longer that the formula... for higher beam tilt, make them 2% shorter.... One more thing... A quarter wave has somewhere around 20-40 ohms impedance (depending on the ground side of the antenna... ie radials, car roof...etc.) so you want the antenna to match the impedance of the cable/antenna port of the radio..... so.... If the impedance along a feed line repeats itself every 1/2 wave.... AND you use 1/2 wave elements.... Then you need a 1/4 wave whip at the top of the collinear.... Remember the input connector to most RTL dongles are 50 ohms.... try not to change this in your feed line and antenna.... (Hint...RG6* is 75 ohms.... why do you use it?)... answer, its cheap, easy to assemble with the solid conductor... and "F" connectors are good to 4GHZ.... So many things to think about, so little time!!!

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