Wont work if USB cable is too long.
In most cases this will require outdoor installation of Pi, within few meters of prostick+antenna.
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Try the RTL-SDR Blog pre-amp/filter combo.
https://www.rtl-sdr.com/new-product-rtl-sdr-blog-1090-mhz-ads-b-lna/
This is a good option if PoE is used, or Wi-Fi (if distance is not an obstacle) with power taken to the mast, or better still, a solar panel/battery setup.
Will require a water-proof box to house the Pi and PoE Splitter, as both will be outdoors near the antenna.
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Yes… I thought that was assumed and not an issue.
It is feed trough the two points on the side of the board with 5Vdc.Ground is common with the cable shield, so it would need just another wire wrapped around the coax. I trust that better than injection in the cox, no losses of RF.
The variant with power over coax would require just adding an inductance (coil) between the output terminal and the +Vcc terminal.
If the receiver does not support bias T, use this little board from, where else, eBay.
This topic needs to end.
A Preamp is ONLY good if you have a long coax run, and that is itself a crazy idea, when USB receivers and raspberry pi’s can be mounted at the antenna, either with POI or just run AC or DC up to the antenna.
I’ve done all three. I’ve also used this pre-amp and it only generated so much RF that it desensitized the receiver that lowered not raised the number of received signals.
The solution to more signals is simply a better antenna or multiple antennas to thru a power divider to raise gain… and that’s a never ending battle and or story.
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???
There is some merit to using a good pre-amp regardless, and that is the reduction of the dongle’s built-in gain. It’s not a good idea to ‘run full throttle’.
Waiting for your promised post for 15 dBi DIY antenna.
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My "15Dbi " did not work as well as a 3dbi… back to the drawing boards
to figure out what went wrong.
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That is what this hobby is all about. If you first don’t succeed, try, try again.
My experimental antenna is a cantenna and without a pre-amp I get 125 mile coverage. Pre amp, 200 mile coverage.I tried the spider with success and the coax co-linear with marginal success. Make sure your coax connections are proper and coax selection is good. I feed with RG6 CATV line and LMR400 too.
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If at first you don’t succeed, parachuting is not for you!
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My results disagree with that. I’m running a FlightAware external antenna indoors → 1m CLF200 coax → Uputronics SAW filtered preamp → Pro Stick Plus → RPi, all sitting indoors on a windowsill. Adding the preamp increased positions and aircraft and range immediately. This arrangement is a very quick and convenient way to improve things, and the preamp is available to improve things further if/when the antenna goes on the roof.
I agree it’s not a panacea for a bad setup, but it’s certainly useful beyond the example you gave.
With the preamp in place I’ve improved aircraft and range even further by changing gain from default -10 to 49.6 as detailed here. I found that positions actually went down in some cases, while aircraft and range simultaneously went up.
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For LNA important parameter is NF.
For example
PGA-103+ : Low Noise Figure, 0.6 at 1 GHz; 0.9 dB at 2 GHz
SPF-5189Z : Noise Figure 0.55 dB at 0.9 GHz
MGA-82563 : Noise Figure at 1.0 GHz
And by way about needed or not LNA for setup -
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FILTERED preamps are not the same as preamps! There is no use for a plain preamp if you have a half-decent antenna.
Sure filters help in a world full of cell towers, but that’s a different issue altogether.
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The manufacturers must cover as many potential customers as possible. A lot of them live in places where a good quality filter is needed. The others have nothing major to lose, if they use a good quality filter, but no interfering signal. Sure, there are additional losses, and if the signal chain is border line to begin with, it may be the last straw to break the camel’s back.
As I mentioned elsewhere, there is merit in using a good quality preamp. Not only long cable runs installations can benefit from it, but also lowering the built-in gain in basic receivers like the RTL-SDR dongles can benefit.
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Hi
I use this one with rtl sdr v 3
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F112940507293
Good reception
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Sometimes you try to get more but find out your maxed out for your location, I have tried putting cheap chinese preamps and filters etc. which only reduced the plane count, i now use a blue FA stick and a FA antenna on a short piece of coax to a rasp pi. I get 298NM max according to Airnav doubt i can do better from my location.