AirNav Systems Forum
AirNav RadarBox and RadarBox24.com => AirNav RadarBox and RadarBox24.com Discussion => Topic started by: GlynH on November 20, 2020, 12:22:28 PM
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Hi there,
Although I haven't seen it in years back in 2008 I bought a Kuhne 1090 LNA and briefly fitted it at the mast top way back when I was using the original RadarBox hardware device.
Unfortunately it had the opposite effect of by actually reducing the amount of aircraft that I could see in MyFlights instead of the expected increase!
This I put down to the boosted signal overloading the front end of the RadarBox and so I reverted to feeding it from my external Watson Radar Extender via 5m of Westflex 103 directly into the RadarBox through an N-SMA adaptor.
Although I am pleased with my current Max Range of 295Nm and Avg Range of 219Nm located 150m ASL part of me wonders what the effect of the Kuhne might have these days when feeding the AirNav FlightStick?
It could go one of two ways as I see it;
1. As above where the boosted signal swamps the receivers front end as I also believe the FlightStick has its own LNA & filter built-in doesn't it?
2. If the receiver has become hardened through the years by better design, components etc. the extra signal strength could achieve its intended purpose by increasing the range and by definition the amount of aircraft I can see.
Does anybody have any experience or indeed theories about what adding the Kuhne might bring to the party?
I ask because its a lot of hassle going up a ladder (especially at my age although I will probably be press-ganged into putting the Christmas lights up again soon) but especially in slackening off the clamps, dropping the pole bit-by-bit, cutting the cable ties of one-by-one until the antenna comes within reach, disconnecting, fitting the LNA, reconnecting and going through the reverse process with the antenna pole.
I see from the Kuhne website that the current model is now called -2 so guessing that's been redesigned/improved since my day although I don't know what the differences might be?
I may even end up with the MKII version if I can't find my original item and deem it a worthwhile exercise...
Thanks & kind regards,
-=Glyn=-
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As the Flightstick has already got an LNA built in I dont see how adding another would assist. I have no knowledge on this but to amplify an already amplified signal would to me cause issues and possibly make things worse
Alan
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Yeah that's what I figured Alan if it goes the way of 1. above which is where it would probably end up.
As a Sound Engineer in a previous life I was always careful when it came to gain staging and outputs especially on analogue desks and I apply a similar logic when it comes to the receiving chain.
Without lots of experimentation with/without the Kuhne and maybe the ANFS vs a device without a built-in LNA if there is even such a beast I guess I will never know for sure and to be honest I don't like the idea of all that faffing around which was why I wondered if anyone had been down this road before.
I'm at the stage where I have been making compromises on performance vs convenience for a number of years now (with most things anyhow) and as performance isn't really an issue here would probably rather not wring its neck to extract that last ounce as its usually a case of diminishing returns where price/effort goes up exponentially.
Until I change my mind of course...:)
I should just sit back end enjoy what I have instead of looking for ways to make it go faster!
-=Glyn=-
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@GlynH
Ask this question in flightaware forum, which has a large number of members experienced in in hardware & Linux software, and most are keen to help others with their experience/knowledge.
Also, the author of dump1090-mutability and dump1090-fa (Oliver B Jowett aka obj) is a regular visitor there and answeres Linux/RPi related issues.
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I'll do that...thanks.
Enjoy your weekend!
Kind regards,
-=Glyn=-