Adjusting the SatNOGS Client - Revision history

Vk5qi: /* SatNOGS station adjustments */

2020-11-07T10:25:53Z

‎SatNOGS station adjustments

Vk5qi: /* SatNOGS station adjustments */

2020-06-05T08:45:16Z

‎SatNOGS station adjustments

Vk5qi: /* Waterfall color improvements */ Remove obsolete waterfall range instructions.

2020-06-05T08:35:23Z

‎Waterfall color improvements: Remove obsolete waterfall range instructions.

Vk5qi: /* automatic adjustment via kalibrate-rtl */

2020-06-05T08:17:44Z

‎automatic adjustment via kalibrate-rtl

Fredy: /* manual adjustment */

2020-06-05T05:54:11Z

‎manual adjustment

Jebba: categories

2020-01-19T21:53:40Z

Cweiss: /* automatic adjustment via kalibrate-rtl */ I needed to install M4 and Automake in order to successfully run the bootstrap command on the current image.

2019-05-26T02:14:36Z

‎automatic adjustment via kalibrate-rtl: I needed to install M4 and Automake in order to successfully run the bootstrap command on the current image.

Dren.imeraj: Title styling update

2019-04-30T21:16:26Z

Title styling update

Dren.imeraj: Added entry for frequency adjustment using observations

2019-04-30T21:15:44Z

Added entry for frequency adjustment using observations

Audioman: Add mention about rounding ppm correction

2018-11-08T17:58:51Z

Add mention about rounding ppm correction

@@ Line 11: / Line 11: @@
 *you've installed [http://gqrx.dk/download install gqrx] on your local computer.
-==SatNOGS station adjustments==
+==Frequency Offset Calibration==
-Now you've come to a point where you want to know how well your station is performing.  The first step is to determine your frequency offset.
+Some cheaper SDRs may have a significant frequency offset, due to the use of poor quality reference crystal oscillators. This can result in observations which may be un-decodable. If you see observations that have signals that appear to be 'off to one side', then you should perform some of the steps below to determine your offset.
-===automatic adjustment via kalibrate-rtl===
+{{Message|Note: SDRs which use a 'standard' crystal, without temperature compensation (e.g. the cheaper RTLSDRs) will drift noticeably in frequency with temperature changes. This means any calibration values determined below will not be consistent. It is highly recommended that you purchase a SDR which utilises a temperature compensated crystal oscillator (TCXO).}}<br />
 As a more comfortable way to get the ppm of your SDR the tool ''kal'' from https://github.com/viraptor/kalibrate-rtl can be used.
 At the moment you probably have to get and build it by yourself.
-'''Note: This is only going to work if GSM is still in existence in your country. If (like Australia), your country has moved on from the 1990s and deprecated GSM, you will need to use another option (scroll down).'''
+'''Note: This is only going to work if GSM is still in existence in your country. If (like Australia), your country has moved on from the 1980s and deprecated GSM, you will need to use another option (scroll down).'''
 When using the pre-built image for the Raspberry Pi, you have
@@ Line 99: / Line 101: @@
 Now enter the measured ppm in satnogs-setup and you're done. The value should be entered without decimals, for example -1.
-=== Automatic Adjustment using LTE Signals ===
+===Automatic Adjustment using LTE Signals===
 If you are living in a country where GSM is no longer present, but LTE is available (in a frequency range supported by your receiver), then you can determine your SDR's PPM offset by following this guide: https://gist.github.com/darksidelemm/b517e6a9b821c50c170f1b9b7d65b824
@@ Line 105: / Line 107: @@
 If you cannot calibrate against GSM or LTE towers, but you have a nearby amateur radio beacon or transmitter at a reasonably well-known frequency, you can use this to obtain at least a coarse PPM correction.
-'''NOTE: This section may need to be updated to follow the same process as is used in `Setting The Gain`, as rtl_tcp may not be available on the latest SatNOGS RPI images.'''
+'''NOTE: This section needs to be updated to follow the same process as is used in `Setting The Gain`, as rtl_tcp may not be available on the latest SatNOGS RPI images, and will not work if any other SDR type is in use.'''
 SSH to your SatNOGS Pi with your well-known user account; by default, this is the user "pi".  After successful authorization you will see a prompt like this:<pre>

@@ Line 99: / Line 99: @@
 Now enter the measured ppm in satnogs-setup and you're done. The value should be entered without decimals, for example -1.
-===manual adjustment===
+=== Automatic Adjustment using LTE Signals ===
-'''This method was used in older version of satnogs-client and is not available in the current stable one.'''
+If you are living in a country where GSM is no longer present, but LTE is available (in a frequency range supported by your receiver), then you can determine your SDR's PPM offset by following this guide: https://gist.github.com/darksidelemm/b517e6a9b821c50c170f1b9b7d65b824
-To start, please connect to your Raspberry Pi's local web interface. By default the URL is something like "http://192.168.0.5:5000"; you'll need to figure out what it is for your client. In the upper right corner there is a big green button where you can set your ground station in standalone mode.
+===Manual Adjustment using GQRX===
-Here's how it looks in network mode:
+'''NOTE: This section may need to be updated to follow the same process as is used in `Setting The Gain`, as rtl_tcp may not be available on the latest SatNOGS RPI images.'''
-<p>[[File:SatNOGS_local_network_mode.png|center|600px]]</p>
+SSH to your SatNOGS Pi with your well-known user account; by default, this is the user "pi".  After successful authorization you will see a prompt like this:<pre>
   Linux satnogs190-dev 4.9.59-v7+ #1047 SMP Sun Oct 29 12:19:23 GMT 2017 armv7l
@@ Line 137: / Line 120: @@
 </pre>
 Now go ahead and start the "RTL SDR spectrum server":
@@ Line 218: / Line 203: @@
 <p>[[File:Gqrx_running.png|center|600px]]</p>
-Go for a known local HAM radio repeater or a CW beacon transmitter and set your demodulator accordingly. Narrow Band FM or CW is best to discover ppm error offset, which is the frequency offset in parts per million (ppm) which is always there with standard RTL-SDR dongles. It is also highly temperature dependent, so one might have to re-evaluate this from time to time. Enter the known frequency of your chosen transmitter (NFM repaeter or CW beacon). I have chosen a very known CW beacon just some km away from my home: ON4VHF on 144.718000 MHz. Walk through the tab called "Receiver options" and change the settings to fit the beacon: "Filter width Normal", "Filter shape Normal", "Mode CW-L", "AGC Medium". Set Squelch to something low, so you can hear noise from your speakers. Maybe you have to Adjust the audio "Gain" to something like "0.0 dB". You can adjust this to fit your needs to hear noise. With ppm error, which is default, set to 0.0 ppm, one can just guess where your receiver is listening. Anyway, just set it to 144.718000 MHz and try to find your beacon. You can see the result for my RTL SDR dongle down here:
+Go for a known local HAM radio repeater or a CW beacon transmitter and set your demodulator accordingly. Narrow Band FM or CW is best to discover ppm error offset, which is the frequency offset in parts per million (ppm) which is always there with standard RTL-SDR dongles. For SDRs without a Temperature Compensated Crystal Oscillator ('TCXO') this value may be temperature dependent. Enter the known frequency of your chosen transmitter (NFM repeater or CW beacon). I have chosen a very known CW beacon just some km away from my home: ON4VHF on 144.718000 MHz. Walk through the tab called "Receiver options" and change the settings to fit the beacon: "Filter width Normal", "Filter shape Normal", "Mode CW-L", "AGC Medium". Set Squelch to something low, so you can hear noise from your speakers. Maybe you have to Adjust the audio "Gain" to something like "0.0 dB". You can adjust this to fit your needs to hear noise. With ppm error, which is default, set to 0.0 ppm, one can just guess where your receiver is listening. Anyway, just set it to 144.718000 MHz and try to find your beacon. You can see the result for my RTL SDR dongle down here:
 <p>[[File:Gqrx_ppm-error_offset.png|center|600px]]</p>

@@ Line 260: / Line 260: @@
 ==Enhancements==
-===Waterfall color improvements===
+===Waterfall Color improvements===
-To get some nicer waterfalls one has to dig into waterfall plotting script. This is a static one and, so far, cannot be configured through satnogs-setup. Anyway: there is no magic behind it and one can understand what the changes are once you have seen them.
+By default the SatNOGS client will adjust the waterfall colour ranges to best display the received signal.
-Log into the Pi and start at making a copy of /usr/share/satnogs/scripts/satnogs_waterfall.gp, just in case:
+If desired, this auto-ranging can be disabled by running <code>sudo satnogs-setup</code>, and navigating to <code>Advanced -> Waterfall</code>. From here the auto-ranging can be turned off, and the minimum and maximum waterfall colour-scale levels can be set.
 [[Category:Software]]
 [[Category:Operate]]

@@ Line 19: / Line 19: @@
 As a more comfortable way to get the ppm of your SDR the tool ''kal'' from https://github.com/viraptor/kalibrate-rtl can be used.
 At the moment you probably have to get and build it by yourself.
 When using the pre-built image for the Raspberry Pi, you have

← Older revision		Revision as of 05:54, 5 June 2020
Line 98:		Line 98:

	===manual adjustment===		===manual adjustment===
		+	'''This method was used in older version of satnogs-client and is not available in the current stable one.'''

	To start, please connect to your Raspberry Pi's local web interface. By default the URL is something like "http://192.168.0.5:5000"; you'll need to figure out what it is for your client. In the upper right corner there is a big green button where you can set your ground station in standalone mode.		To start, please connect to your Raspberry Pi's local web interface. By default the URL is something like "http://192.168.0.5:5000"; you'll need to figure out what it is for your client. In the upper right corner there is a big green button where you can set your ground station in standalone mode.

← Older revision		Revision as of 21:53, 19 January 2020
Line 1:		Line 1:
		+	==Introduction==
		+
	(This page is a port of [https://community.libre.space/t/how-to-do-some-client-adjustments/1604/1 DL4PD's excellent post] to the SatNOGS forum.)		(This page is a port of [https://community.libre.space/t/how-to-do-some-client-adjustments/1604/1 DL4PD's excellent post] to the SatNOGS forum.)

Line 290:		Line 292:

	Save the file and you are done. Schedule some observations and watch the new colors. Maybe you can just improve it a little more but keep in mind: always keep a bit of the noise floor into the waterfalls, so you can see the whole signals dynamic range. I love it, when there are only a few dots of the noise.		Save the file and you are done. Schedule some observations and watch the new colors. Maybe you can just improve it a little more but keep in mind: always keep a bit of the noise floor into the waterfalls, so you can see the whole signals dynamic range. I love it, when there are only a few dots of the noise.
		+
		+	[[Category:Software]]
		+	[[Category:Operate]]

@@ Line 20: / Line 20: @@
 When using the pre-built image for the Raspberry Pi, you have
 to install the following dependencies:
-  $ sudo apt-get install libtool pkg-config libfftw3-dev librtlsdr-dev
+  $ sudo apt-get install libtool pkg-config libfftw3-dev librtlsdr-dev automake m4
 Then you can build and install it with

@@ Line 235: / Line 235: @@
 {{Message|With gqrx, you get a nice tool to do some SDR stuff by the way. Just play around a bit and get familiar with all that stuff. Just keep in mind that, as long as you run the RTL SDR Spectrum server or you have set your client into standalone mode, nothing is done from network.}}
-=== '''adjustment using observations''' ===
+===adjustment using observations===
 Another way of adjusting the frequency offset is by making an observation of a satellite that transmits CW. Once the observation is complete, the CW signal from the satellite should look like a straight line at 0Hz on the observation waterfall. If there's a frequency offset, the signal will be off-center. The image below shows observation details for a CW transmitter on VHF. Since the frequency offset is not yet adjusted, the CW signal is present between the -10kHz and 0Hz markers.
 {{Message|It is possible for the CW signal to appear at a frequency above the 10kHz tick or below the -10kHz tick. In that case, use the frequency of the first tick with a higher absolute value frequency than the CW signal absolute value frequency. Do not forget to update the selected tick frequency in the equations below!}}<br />

@@ Line 1: / Line 1: @@
 (This page is a port of [https://community.libre.space/t/how-to-do-some-client-adjustments/1604/1 DL4PD's excellent post] to the SatNOGS forum.)
-== Prerequisites / dependencies ==
+==Prerequisites / dependencies==
 This page assumes:
-* you've read all the [[Get Started|Getting Started]] page, as well as the pages linked under "Build" and "Operate" on the [[Main Page]]
+*you've read all the [[Get Started|Getting Started]] page, as well as the pages linked under "Build" and "Operate" on the [[Main Page]]
-* you've already made your [[Operation|first observations]] and have some waterfalls in the [[Network]]
+*you've already made your [[Operation|first observations]] and have some waterfalls in the [[Network]]
-* you've installed [http://gqrx.dk/download install gqrx] on your local computer.
+*you've installed [http://gqrx.dk/download install gqrx] on your local computer.
-== SatNOGS station adjustments ==
+==SatNOGS station adjustments==
 Now you've come to a point where you want to know how well your station is performing.  The first step is to determine your frequency offset.
-=== automatic adjustment via kalibrate-rtl ===
+===automatic adjustment via kalibrate-rtl===
 As a more comfortable way to get the ppm of your SDR the tool ''kal'' from https://github.com/viraptor/kalibrate-rtl can be used.
@@ Line 95: / Line 95: @@
 Now enter the measured ppm in satnogs-setup and you're done. The value should be entered without decimals, for example -1.
-=== manual adjustment ===
+===manual adjustment===
 To start, please connect to your Raspberry Pi's local web interface. By default the URL is something like "http://192.168.0.5:5000"; you'll need to figure out what it is for your client. In the upper right corner there is a big green button where you can set your ground station in standalone mode.
@@ Line 235: / Line 235: @@
 {{Message|With gqrx, you get a nice tool to do some SDR stuff by the way. Just play around a bit and get familiar with all that stuff. Just keep in mind that, as long as you run the RTL SDR Spectrum server or you have set your client into standalone mode, nothing is done from network.}}
-== Enhancements ==
+=== '''adjustment using observations''' ===
-=== Waterfall color improvements ===
+==Enhancements==
 To get some nicer waterfalls one has to dig into waterfall plotting script. This is a static one and, so far, cannot be configured through satnogs-setup. Anyway: there is no magic behind it and one can understand what the changes are once you have seen them.

← Older revision		Revision as of 17:58, 8 November 2018
Line 93:		Line 93:


−	Now enter the measured ppm in satnogs-setup and you're done.	+	Now enter the measured ppm in satnogs-setup and you're done. The value should be entered without decimals, for example -1.

	=== manual adjustment ===		=== manual adjustment ===