PilotAware
British Forum => Technical Support => Topic started by: Jumpy07 on September 04, 2018, 04:23:21 pm
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Have setup a new basic ground station, RPI, with 820T dongle and home made BI quad antenna located in my loft.
Based just on edge of Glasgow CTR at southern end of Loch Lomond.
I think I have it setup correctly.. but not seeing anything.. that said most of the GA traffic, ML, HG etc.. come out to play over the Loch at the weekends.
I am a 360 radar MLAT and ADS-B feeder.. couple of RPI's setup running for a few months now..
This is the stats from the webpage off the RPI:
RTLSDR OGN demodulator and decoder 0.2.6.RPI-GPU/Mar 31 2017
System
Host name ogn-receiver
Configuration file path+name /home/pi/rtlsdr-ogn.conf
Local time 15:14:21
Software RTLSDR-OGN 0.2.6.RPI-GPU
CPU load 1.3/1.2/1.1
RAM [free/total] 42.1/188.7 MB
CPU temperature +51.9 ℃
NTP UTC time 15:14:21
NTP est. error 0.1 ms
NTP freq. corr. -10.06 ppm
Position
Position.Latitude +55.99000 deg
Position.Longitude -004.57200 deg
Position.Altitude 5 m
Position.GeoidSepar +55 m
RF
RF.FreqPlan 1: Europe/Africa
RF input noise -1.1 dB
Demodulator
Demodulator.DetectSNR 10.0 dB
Demodulator.PipeName ogn-rf.fifo
Demodulator.ScanMargin 20.0 kHz
Traffic rates [visible/all]
Aircrafts received over last 12 hours 0/ 0
Aircrafts received over last hour 0/ 0
Aircrafts received over last minute 0/ 0
Positions received over last minute 0/ 0
APRS
APRS.Server[0] -> aprs.glidernet.org:14580
connected to 37.187.40.234:14580
connected for 10h11
KiloBytes sent/received 21/138
APRS.Call LOCHLMND
APRS.Icon I&
APRS.FilterRange 0.0 km
APRS.Beacon.Interval 300 sec
APRS.Status.Interval 300 sec
APRS.MaxBitError 16 bit
APRS.HighResolution 1
APRS.SAR 1
APRS.PositionInterval 20 sec
APRS.MaxDistError 20 m
APRS.ReportDelay 5 sec
DDB
DDB.RefreshInterval 0
DDB.UseAsWhitelist 0
APRS beacon:
LOCHLMND>APRS:/151014h5559.40NI00434.32W&/A=000016
APRS status:
LOCHLMND>APRS:>151014h v0.2.6.RPI-GPU CPU:1.1 RAM:41.3/188.7MB NTP:0.1ms/-10.1ppm +52.5C 0/0Acfts[1h] RF:+20+149.5ppm/-1.09dB
RF spectrograms: OGN
List of aircrafts being tracked: long or short
RTLSDR OGN RF processor 0.2.6.RPI-GPU/Mar 31 2017
System
Host name ogn-receiver
Configuration file path+name /home/pi/rtlsdr-ogn.conf
Local time 15:20:30
Software 0.2.6.RPI-GPU
CPU load 1.2/1.1/1.1
RAM [free/total] 41.7/188.7 MB
CPU temperature +51.4 ℃
NTP UTC time 15:20:30
NTP est. error 0.1 ms
NTP freq. corr. -10.06 ppm
RTL-SDR device #0
Name Generic RTL2832U OEM
Tuner type R820T
Manufacturer Realtek
Product RTL2838UHIDIR
Serial 00000001
Center frequency 868.303 MHz
Sample rate 1.000 MHz
Frequency correction +169.5 ppm
Life Time 97.1% ppm
RTL Xtal 28.800575 MHz
Tuner Xtal 28.800575 MHz
RF
RF.FreqPlan 1: Europe/Africa
RF.Device 0
RF.SampleRate 1.0 MHz
RF.FreqCorr +20 ppm
RF.FreqRaster 28125 Hz
RF.OffsetTuning 0
Fine calib. FreqCorr +149.5 ppm
RF.PulseFilter.Threshold 0
RF.PulseFilter duty 0.0 ppm
RF.OGN.GainMode 1
RF.OGN.Gain 60.0 dB
RF.OGN.StartTime 0.375 sec
RF.OGN.SensTime 0.850 sec
RF.OGN.SaveRawData 0 sec
RF.GSM.CenterFreq 950.0 MHz
RF.GSM.Gain 49.6 dB
RF.GSM.SensTime 0.250 sec
RF spectrograms: OGN
GSM frequency calibration
RF raw data of a time-slot (8-bit unsigned I/Q) - a 2 MB binary file !
I ran the GSM cal and tweaked the gain and freq for best results..
Does this look okay ?
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Your frequency correction is wrong, what type of dongle are you using? If it is one with a TCXO then the correction should be close to zero, the cheap Chinese ones have corrections as high as 50-60 but never as high as 169.5 the problem often arises when running the default GSM scan as it expects a stick with an offset around 50, with a TCXO stick the scan fails to go down low enough so it locks on to the next highest GSM signal and gives an incorrect offset, try stopping the OGN service and re-run the GSM scan with an initial offset of zero, (you cannot run the scan if the OGN service is still running)
Also unless you are in an area with very poor GSM coverage then you should probably reduce the GSM gain, somewhere around 20-25 is usually sufficient once the offset is correct.
Other than that it all looks pretty good.
Ben. (Aldersht2 / PWAldersh)
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Is this an OGN or OGNR ?
I dont see a pilotaware feed to the APRS
Also there is a section on the forum for OGN
Thx lee
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Your frequency correction is wrong, what type of dongle are you using? If it is one with a TCXO then the correction should be close to zero, the cheap Chinese ones have corrections as high as 50-60 but never as high as 169.5 the problem often arises when running the default GSM scan as it expects a stick with an offset around 50, with a TCXO stick the scan fails to go down low enough so it locks on to the next highest GSM signal and gives an incorrect offset, try stopping the OGN service and re-run the GSM scan with an initial offset of zero, (you cannot run the scan if the OGN service is still running)
Also unless you are in an area with very poor GSM coverage then you should probably reduce the GSM gain, somewhere around 20-25 is usually sufficient once the offset is correct.
Other than that it all looks pretty good.
Ben. (Aldersht2 / PWAldersh)
Alloy 820T.. ie: the better one.. have set the offset to zero and gain to 20, will see what tomorrow brings.
Many thanks for the reply and pointer
Craig
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Is this an OGN or OGNR ?
I dont see a pilotaware feed to the APRS
Also there is a section on the forum for OGN
Thx lee
OGN, should be on the list can see the station on the map and have added it to the station list (LOCHLMND)
Cheers
Craig
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Hi Craig
If it is a vanilla OGN station you may be better joining the google group
Open Glider Network
This is specifically for OGN support, whereas here we are only really concerned with the additional support of the PilotAware Rebroadcast - OGB-R
if you want to add PilotAware Rebroadcast capability, then please email
ogn@pilotaware.com
Thx
Lee