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 Post subject: Re: Gain Adjustment...
PostPosted: Sun Apr 02, 2017 2:32 pm 
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biekerc - FlightAware user avatar

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Not sure there is a way read out the value, but you do not really have to. It sets a gain value which is slightly higher than you can set manually, which means above 49.

Because of the nature of the ADS-B signals, the AGC ends setting the highest possible value, and due to a bug somewhere this even higher than you can manually. For more detail, just search around in this forum, obj who maintains dump-fa and piaware, has written on this on serval occasions


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 Post subject: Re: Gain Adjustment...
PostPosted: Sun Apr 02, 2017 2:38 pm 
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abcd567 - FlightAware user avatar

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-10 is a special value meaning "turn on AGC".
Because of the nature of ADS-B signals, for ADS-B the AGC doesn't actually give auto-gain, just a high gain.
Usually AGC will behave like "more gain than max", i.e. more than 49.6 dB.

Please see comments by Oliver (obj) linked below:

post203260.html#p203260

post203208.html#p203208


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 Post subject: Re: Gain Adjustment...
PostPosted: Tue Apr 04, 2017 9:49 am 
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abcd567 - FlightAware user avatar

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After upgrade of Piaware and dump1090-fa to 3.5, now "--gain -10", which used to show "rtlsdr gain set to 0.00" is now showing "rtlsdr: enabling tuner AGC"

Quote:
pi@orangepipc:~$ sudo systemctl status dump1090-fa -l
[sudo] password for pi:
● dump1090-fa.service - dump1090 ADS-B receiver (FlightAware customization)
Loaded: loaded (/lib/systemd/system/dump1090-fa.service; enabled)
Active: active (running) since Tue 2017-04-04 10:23:20 EDT; 7min ago
Docs: https:// flightaware.com/adsb/piaware/
Main PID: 429 (dump1090-fa)

CGroup: /system.slice/dump1090-fa.service
└─ 429 / usr / bin / dump1090-fa --device-index 0 --gain -10 --ppm 0 --net-bo-port 30005
--max-range 360 --net --net-heartbeat 60 --net-ro-size 1000 --net-ro-interval 1 --net-ri-port 0 --net-ro-port 30002 --net-sbs-port 30003 --net-bi-port 30004,30104 --net-bo-port 30005 --json-location-accuracy 1 --lat 43.5xxxx --lon -79.6xxxx --write-json /run/dump1090-fa --quiet

Apr 04 10:23:20 orangepipc systemd[1]: Started dump1090 ADS-B receiver (FlightAware customization).
Apr 04 10:23:20 orangepipc dump1090-fa[429]: Tue Apr 4 10:23:20 2017 EDT dump1090-fa 3.5.0 starting up.
Apr 04 10:23:20 orangepipc dump1090-fa[429]: rtlsdr: using device #0: Generic RTL2832U OEM (Realtek, RTL2838UHIDIR, SN 00000001)
Apr 04 10:23:21 orangepipc dump1090-fa[429]: Found Rafael Micro R820T tuner
Apr 04 10:23:21 orangepipc dump1090-fa[429]: rtlsdr: enabling tuner AGC


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 Post subject: Re: Gain Adjustment...
PostPosted: Fri Apr 07, 2017 5:03 am 
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MikeMathee - FlightAware user avatar

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wittrup58 wrote:
abcd567 wrote:
(1) Install Python:
pi@piaware:~$ sudo apt-get install python

(2) Create new blank file:
pi@piaware:~$ sudo nano optimize-gain-piaware3.py

(3) Copy code in my post for Piaware 3.0.4 image on page 3 of this thread (CLICK HERE), and paste it in newly created file "optimize-gain-piaware3.py". Save file.

(4) Make executable the file "optimize-gain-piaware3.py"
pi@piaware:~$ sudo chmod +x optimize-gain-piaware3.py

(5) Run the code
pi@piaware:~$ sudo ./optimize-gain-piaware3.py
test 1 of 5
gain= 49.6 messages= 10304 positions= 755 planes= 62
.........
.........

Untested! Should work...
Replace step 2 & 3 with:
Code:
pi@piaware:~$ wget https://raw.githubusercontent.com/wittrup/piawarebash/master/pyh/optimize-gain-piaware3.py


What changes needs to be made to the script for it to work on the dump1090-fa package install?


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 Post subject: Re: Gain Adjustment...
PostPosted: Sun Apr 09, 2017 4:54 am 
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biekerc - FlightAware user avatar

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Mmmh, I just bought a cavity filter, which led me to testing different gain settings (with and without the filter) via the script, mostly using 4 different values, 5 runs each 60s, if I read the option values correctly.

The results indicates that a gain value around 28 should be the best. Here is the result of one run, others had the same results.

%s ===To tals=== Sat Apr 08 12:41:53 UTC 2017
Sat Apr 08:12:41 :53 UTC 2017
GAIN MSG POS ADR TIME
49.6 128621 5038 5
38.6 148817 5765 5
28.0 204456 8252 5
20.0 179522 7353 5

So I changed the gain, let it run for a while, then change back to -10, the highest possible value, and immediately I see more a/c and m/s on skyview? This actually happend before, any idea what could be the reason for this? The setup is a Pro Stick Plus and FA antenna located in the attic.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sun Apr 09, 2017 5:20 am 
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rsmath - FlightAware user avatar

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obj wrote:
This thread is more about automatically finding the "right value" but you can always do manual trial-and-error.


I wanted to followup to thank you for your response on how to set the gain value manually. I've tried various gain values by manual trial and error over a few days and found 44.5 seems to be working the best.


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 Post subject: Re: Gain Adjustment...
PostPosted: Tue May 02, 2017 5:57 am 
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Hi Guys,

Same subject so i thought easiest to resurrect an old post !
I'm just seeking some advice / guidance on the 'optimum' gain for my setup - any and all thoughts / comments would be most welcome !

26" FA Antenna on pole above the roof -> 6m LMR400 -> N to SMA adapter -> (Optional FA Filter) -> Orange FA Stick -> RPi3 (Wifi, but could be cabled if it helps).

Running the gain test scripts for 15 seconds per gain value (with and without filter) gives me:

Image

So, from those scores I concluded that i should set my gain at 38.6 and include the filter.
But, looking at the graph of the received signal strength for the last 45 minutes or so, this looks like its higher than optimal - hence my confusion.

Image

What do you folks think / what would you do ?

Cheers !!

Greg


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 Post subject: Re: Gain Adjustment...
PostPosted: Tue May 02, 2017 9:26 am 
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conligwx - FlightAware user avatar

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you should also run the tests with -10 setting too or was that the "max" setting? I ran similar tests but in my circumstances -10 was better.


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 Post subject: Re: Gain Adjustment...
PostPosted: Tue May 02, 2017 2:04 pm 
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sloefkesloeber - FlightAware user avatar

Joined: Sun Mar 22, 2015 4:38 am
Posts: 10
15 seconds pro gain is to short. I played some with it and I need +/- 45 seconds to have a real full view
Look at the signals received and you see it climbing ... and in my case 45 seconds is a nice compromise to have a stable number
shorter then that the results are .. un even to say


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 Post subject: Re: Gain Adjustment...
PostPosted: Tue May 02, 2017 2:25 pm 
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GergMcHairy - FlightAware user avatar

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Quote:
15 seconds pro gain is to short.
Thanks sloefkesloeber, that's a very good point...
I've added -10 to the list too - thanks conligwx

I'm re-running now !

Greg


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 Post subject: Re: Gain Adjustment...
PostPosted: Wed May 03, 2017 10:52 am 
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GergMcHairy - FlightAware user avatar

Joined: Mon Mar 20, 2017 10:26 am
Posts: 17
So, if anyone is interested - after some 7.5 hours testing (40 runs of 15 gain settings @ 45 secs each!) its a ridiculously close run thing.

But 44.5dB is the winner for me !

Image

I'll leave it running with this gain for a few hours and see what the signal strength looks like (not that I'm too worried now as I know which came out on top).

Cheers !

Greg

PS. I note a huge difference between the no. of messages received and the number of positions - is this normal ?


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 Post subject: Re: Gain Adjustment...
PostPosted: Wed May 03, 2017 11:50 am 
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obj - FlightAware user avatar

Joined: Tue Sep 30, 2014 7:14 pm
Posts: 3672
GergMcHairy wrote:
PS. I note a huge difference between the no. of messages received and the number of positions - is this normal ?

Sure, position messages are a relatively small fraction of total Mode S traffic. Each ADS-B equipped aircraft transmits 2 positions/second.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat May 27, 2017 4:37 am 
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alleyoopie - FlightAware user avatar

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Posts: 13
I ran the script on the Pi of a friend (v3.5.0) but I got a 'no such file or directory' error when Python tried to access piaware-config.txt so I guess v3.5.0 is no longer using this file.
How do I proceed, is there a new version of this script available?

Edit: changed the filename in the script to /etc/default/dump1090-fa and this will work.


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 Post subject: Re: Gain Adjustment...
PostPosted: Mon Jun 05, 2017 2:28 pm 
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marianowadel - FlightAware user avatar

Joined: Mon Jun 05, 2017 8:43 am
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Location: La Plata, Buenos Aires, Argentina
Thank you very much for your script @BartJr :D I've been running fr24feed with dump1090 off a R820T (not T2) dongle and recently I installed a Flightaware Pro Stick and started feeding also Flightaware. I was kind of frustrated because even with a bandpass filter, I'd often see less planes than with my previous setup. My range increased, but nearby planes' paths appeared chunked.
After running your script I got this results:

===Totals===
Gain, Messages, Positions, Aircraft
49.6 1569 359 15
48.0 1731 375 16
44.5 1966 463 16
42.1 1945 456 17
40.2 1885 443 16
38.6 1817 409 17
36.4 1877 468 17

Now I'm running:
Code:
dump --aggressive --enable-agc --phase-enhance --net --modeac --fix --gain 36.4 --raw --mlat
and it seems to work a whole lot better.

Anyway, here's my setup:

RPi 2 + Flightaware Pro Stick
Homemade 1090mhz bandpass filter (taken from here) + 5mts RG6 coax + homemade collinear antenna (taken from here)
Cheers!


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 Post subject: Re: Gain Adjustment...
PostPosted: Wed Jun 14, 2017 9:41 am 
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skirgetoon - FlightAware user avatar

Joined: Sat Jul 16, 2016 8:23 pm
Posts: 9
Hi I am having a huge issue with hain

Running piaware 3 on a pi2 with DV3 dongle and a 8 element colinear up on roof.
Just bought a uputronics preamp with built in filter but it makes no difference to my aircraft tracked or my splat. I rang and he suggested changing the gain but if I change it from the standard -10 I lose all but one aircraft, I have tried -49 and -44.

I am new to this so please go easy on me :D


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 Post subject: Re: Gain Adjustment...
PostPosted: Wed Jun 14, 2017 11:58 am 
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obj - FlightAware user avatar

Joined: Tue Sep 30, 2014 7:14 pm
Posts: 3672
You want positive gain values. The usable range is something like 0-50. -10 is a "magic" value. Try 30 or 40 to start with.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 3:34 am 
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davewill2010 - FlightAware user avatar

Joined: Sun May 14, 2017 11:24 am
Posts: 30
MikeMathee wrote:
wittrup58 wrote:
abcd567 wrote:
(1) Install Python:
pi@piaware:~$ sudo apt-get install python

(2) Create new blank file:
pi@piaware:~$ sudo nano optimize-gain-piaware3.py

(3) Copy code in my post for Piaware 3.0.4 image on page 3 of this thread (CLICK HERE), and paste it in newly created file "optimize-gain-piaware3.py". Save file.

(4) Make executable the file "optimize-gain-piaware3.py"
pi@piaware:~$ sudo chmod +x optimize-gain-piaware3.py

(5) Run the code
pi@piaware:~$ sudo ./optimize-gain-piaware3.py
test 1 of 5
gain= 49.6 messages= 10304 positions= 755 planes= 62
.........
.........

Untested! Should work...
Replace step 2 & 3 with:
Code:
pi@piaware:~$ wget https://raw.githubusercontent.com/wittrup/piawarebash/master/pyh/optimize-gain-piaware3.py


OK so running the above and then browsing to "i.p. of my pi":30003 gives me the output below, how do I use that?

MSG,3,1,1,406132,1,2017/07/15,09:34:14.075,2017/07/15,09:34:14.096,,36000,,,52.99731,-1.24077,,,,,,0
MSG,7,1,1,400802,1,2017/07/15,09:34:14.075,2017/07/15,09:34:14.096,,30975,,,,,,,,,,
MSG,7,1,1,405658,1,2017/07/15,09:34:14.077,2017/07/15,09:34:14.096,,24000,,,,,,,,,,
MSG,8,1,1,406443,1,2017/07/15,09:34:14.084,2017/07/15,09:34:14.097,,,,,,,,,,,,0
MSG,6,1,1,4B17E4,1,2017/07/15,09:34:14.085,2017/07/15,09:34:14.097,,,,,,,,5674,0,0,0,
MSG,6,1,1,400802,1,2017/07/15,09:34:14.086,2017/07/15,09:34:14.142,,,,,,,,7726,0,0,0,
MSG,5,1,1,3944F3,1,2017/07/15,09:34:14.089,2017/07/15,09:34:14.143,AFR1687 ,39000,,,,,,,0,,0,
MSG,5,1,1,406443,1,2017/07/15,09:34:14.090,2017/07/15,09:34:14.143,EZY75JQ ,32475,,,,,,,0,,0,
MSG,5,1,1,400802,1,2017/07/15,09:34:14.093,2017/07/15,09:34:14.143,BAW68WG ,30975,,,,,,,0,,0,
MSG,7,1,1,A16883,1,2017/07/15,09:34:14.096,2017/07/15,09:34:14.144,,34000,,,,,,,,,,
MSG,8,1,1,4CA87D,1,2017/07/15,09:34:14.096,2017/07/15,09:34:14.144,,,,,,,,,,,,0
MSG,7,1,1,405B65,1,2017/07/15,09:34:14.096,2017/07/15,09:34:14.144,,37975,,,,,,,,,,
MSG,8,1,1,4CA87D,1,2017/07/15,09:34:14.104,2017/07/15,09:34:14.145,,,,,,,,,,,,0
MSG,6,1,1,3944F3,1,2017/07/15,09:34:14.109,2017/07/15,09:34:14.146,,,,,,,,6332,0,0,0,
MSG,6,1,1,406443,1,2017/07/15,09:34:14.110,2017/07/15,09:34:14.146,,,,,,,,4241,0,0,0,
MSG,5,1,1,406443,1,2017/07/15,09:34:14.111,2017/07/15,09:34:14.146,,32475,,,,,,,0,,0,
MSG,6,1,1,400802,1,2017/07/15,09:34:14.113,2017/07/15,09:34:14.147,,,,,,,,7726,0,0,0,
MSG,7,1,1,4B17E4,1,2017/07/15,09:34:14.114,2017/07/15,09:34:14.147,,20400,,,,,,,,,,
MSG,6,1,1,4B17E4,1,2017/07/15,09:34:14.116,2017/07/15,09:34:14.147,,,,,,,,5674,0,0,0,
MSG,7,1,1,4B17E4,1,2017/07/15,09:34:14.117,2017/07/15,09:34:14.147,,20400,,,,,,,,,,
MSG,8,1,1,405B65,1,2017/07/15,09:34:14.118,2017/07/15,09:34:14.147,,,,,,,,,,,,0
MSG,5,1,1,89644B,1,2017/07/15,09:34:14.119,2017/07/15,09:34:14.147,,33000,,,,,,,0,,0,
MSG,6,1,1,89644B,1,2017/07/15,09:34:14.119,2017/07/15,09:34:14.148,,,,,,,,4755,0,0,0,
MSG,5,1,1,406F9B,1,2017/07/15,09:34:14.125,2017/07/15,09:34:14.148,BEE4LG ,12925,,,,,,,0,,0,
MSG,8,1,1,3944F3,1,2017/07/15,09:34:14.125,2017/07/15,09:34:14.148,,,,,,,,,,,,0
MSG,7,1,1,405658,1,2017/07/15,09:34:14.126,2017/07/15,09:34:14.149,,24000,,,,,,,,,,
MSG,6,1,1,406AE2,1,2017/07/15,09:34:14.127,2017/07/15,09:34:14.149,,,,,,,,7661,0,0,0,
MSG,7,1,1,405658,1,2017/07/15,09:34:14.129,2017/07/15,09:34:14.149,,24000,,,,,,,,,,
MSG,5,1,1,4072C1,1,2017/07/15,09:34:14.131,2017/07/15,09:34:14.149,EZY13PC ,29775,,,,,,,0,,0,
MSG,7,1,1,406666,1,2017/07/15,09:34:14.133,2017/07/15,09:34:14.150,,33000,,,,,,,,,,
MSG,5,1,1,406745,1,2017/07/15,09:34:14.134,2017/07/15,09:34:14.150,BEE365B ,32325,,,,,,,0,,0,
MSG,7,1,1,406666,1,2017/07/15,09:34:14.135,2017/07/15,09:34:14.150,,33000,,,,,,,,,,
MSG,5,1,1,406443,1,2017/07/15,09:34:14.136,2017/07/15,09:34:14.150,,32475,,,,,,,0,,0,
MSG,3,1,1,405B65,1,2017/07/15,09:34:14.139,2017/07/15,09:34:14.150,,37975,,,51.95435,-3.16803,,,,,,0
MSG,4,1,1,406AE2,1,2017/07/15,09:34:14.141,2017/07/15,09:34:14.197,,,416,148,,,-1344,,,,,0
MSG,6,1,1,406F9B,1,2017/07/15,09:34:14.145,2017/07/15,09:34:14.198,,,,,,,,4431,0,0,0,
MSG,7,1,1,406443,1,2017/07/15,09:34:14.147,2017/07/15,09:34:14.198,,32475,,,,,,,,,,
MSG,6,1,1,406745,1,2017/07/15,09:34:14.154,2017/07/15,09:34:14.199,,,,,,,,0660,0,0,0,
MSG,7,1,1,405B65,1,2017/07/15,09:34:14.157,2017/07/15,09:34:14.200,,37975,,,,,,,,,,
MSG,5,1,1,406443,1,2017/07/15,09:34:14.162,2017/07/15,09:34:14.200,,32475,,,,,,,0,,0,
MSG,7,1,1,406F9B,1,2017/07/15,09:34:14.164,2017/07/15,09:34:14.200,,12925,,,,,,,,,,
MSG,7,1,1,3C6494,1,2017/07/15,09:34:14.165,2017/07/15,09:34:14.201,,30025,,,,,,,,,,
MSG,7,1,1,406F9B,1,2017/07/15,09:34:14.168,2017/07/15,09:34:14.201,,12925,,,,,,,,,,
MSG,8,1,1,401152,1,2017/07/15,09:34:14.173,2017/07/15,09:34:14.202,,,,,,,,,,,,0
MSG,5,1,1,89644B,1,2017/07/15,09:34:14.186,2017/07/15,09:34:14.203,,33000,,,,,,,0,,0,
MSG,5,1,1,4072A0,1,2017/07/15,09:34:14.188,2017/07/15,09:34:14.204,,19650,,,,,,,0,,0,
MSG,6,1,1,406443,1,2017/07/15,09:34:14.189,2017/07/15,09:34:14.204,,,,,,,,4241,0,0,0,
MSG,8,1,1,4CA2D4,1,2017/07/15,09:34:14.192,2017/07/15,09:34:14.205,,,,,,,,,,,,0
MSG,8,1,1,405B65,1,2017/07/15,09:34:14.200,2017/07/15,09:34:14.252,,,,,,,,,,,,0
MSG,8,1,1,406132,1,2017/07/15,09:34:14.204,2017/07/15,09:34:14.253,,,,,,,,,,,,0


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 4:26 am 
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davewill2010 - FlightAware user avatar

Joined: Sun May 14, 2017 11:24 am
Posts: 30
Hadnt noticed it actually has given me this in the terminal window:

===Totals=== Sat Jul 15 09:13:09 UTC 2017
Sat Jul 15 09:13:09 UTC 2017 GAIN MSG POS ADR
49.6 184180 9292 145
48.0 182211 9004 141
44.5 180024 9011 138
42.1 181016 9092 139
40.2 174655 9034 134
38.6 171856 8760 132
36.4 173841 8795 136
-10 180556 9164 147
Sat Jul 15 09:13:09 UTC 2017 rtlsdr-gain is unchanged
Sat Jul 15 09:13:10 UTC 2017 ● dump1090-fa.service - dump1090 ADS-B receiver (FlightAware customization)
Loaded: loaded (/lib/systemd/system/dump1090-fa.service; enabled)


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 6:06 am 
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SoNic67 - FlightAware user avatar

Joined: Fri Jun 16, 2017 7:44 pm
Posts: 74
Location: Newport News, Virginia, USA
My take on the gain: there is no magic number. ACG will not help with multiple simultaneous and mobile sources, it is meant for just one fixed source.
Each location is different because the numbers of close-by planes versus far-away planes are different. That means that changing the gain will clip more or less the close-by signals and allow more or less from the far-way signals.
For example, if someone lives close to an airport, it will have lots of strong signals. Lowering the gain will reduce the number of clipped signals and improve the count.
If someone (like me) lives close to a air "highway" it will see the signals simultaneous low (at the maximum range) and high (when the planes are above or closer). I see signals that are -1...-3dB when planes that are closer, to -14dB from the same planes are appearing or disappearing at the maximum range. If there are 40-80 planes on the sky, there will be simultaneous lots with -2dB and lots with -10dB.

What I wonder is what's the lowest negative dB value that will still "work". If I lower the gain by 10dB and the far-away planes are displayed at -25dB for example, will they still be recorded OK?

In my case the range doesn't extend with making the signals "stronger", because of interfering objects with the planes having positions closer to the horizon.

LE: Well, I just changed that value now, the planes at the edge of my range are at -24dB now. Message count increased.
LE2: Lowered the gain 4dB more and message count increased again, significantly. The planes are "disappearing" at -28dB now, but in the same general area (not closer). Not sure, I think there are just more planes in the air at this time, or... is really working. I'll have to run it several days.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 7:42 am 
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obj - FlightAware user avatar

Joined: Tue Sep 30, 2014 7:14 pm
Posts: 3672
Yeah there's a lot of interrelated tradeoffs with gain, noise level, dynamic range etc. There's not really a "one size fits all" solution. When you drop the gain you also reduce the noise floor (and not necessariily by exactly the same amount..), so the demodulator will tend to be able to pick up some weaker (after amplification) signals.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 9:55 am 
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SoNic67 - FlightAware user avatar

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Posts: 74
Location: Newport News, Virginia, USA
For now I will let it run as is with gain lowered approx 14dB (from the Max Gain of approx 55dB).

BTW, how good is the preamp stage (transistor?) inside the FlightFeeder? Great one or just good enough?
As an experiment I might add a good preamp in front of the FF+1090 Filter and then lower even more the gain of FF (to match the introduced gain)... to the purpose of lowering the total noise factor. Of course, it is the risk that amplified signal might overload the input and make things worse.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 11:27 am 
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obj - FlightAware user avatar

Joined: Tue Sep 30, 2014 7:14 pm
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SoNic67 wrote:
BTW, how good is the preamp stage (transistor?) inside the FlightFeeder? Great one or just good enough?

For a FF Orange, it's the same as a prostick.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 12:04 pm 
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abcd567 - FlightAware user avatar

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SoNic67 wrote:
For now I will let it run as is with gain lowered approx 14dB (from the Max Gain of approx 55dB).

BTW, how good is the preamp stage (transistor?) inside the FlightFeeder? Great one or just good enough?
As an experiment I might add a good preamp in front of the FF+1090 Filter and then lower even more the gain of FF (to match the introduced gain)... to the purpose of lowering the total noise factor. Of course, it is the risk that amplified signal might overload the input and make things worse.

Another option: Increasing attenuation
http://discussions.flightaware.com/post202030.html#p202030

.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 15, 2017 1:51 pm 
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I think that the noise of the first stage will decrease more with decreasing amplification, so that's usually a better option. Attenuation in front of it will mean that the gain/noise stays the same and this will decrease the signal/noise ratio.


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 Post subject: Re: Gain Adjustment...
PostPosted: Sat Jul 22, 2017 9:41 pm 
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Hi,

Now I have my FA and mutability versions visually correct (range rings etc, thanks abcd!!) which of these script versions for testing gain, works with 3.5 mutability and fa ??

Jeff


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