I’ve just fitted an LNA to a noolec SDR Smart and configure the Bias T settings but I’m trying to adjust the RF gain and get the following permissions error, has anyone else had this issue and knows how to resolve it? this message appears when I hit save
this issue seems to be when I try to make any changes to any setting
Do you run sudo satnogs-setup ?
Yes I run that via ssh through cmd
If you run sudo you should have all the permissions needed.
Maybe the file system is mounted ro please check with;
mount -l | grep ' / '
That would show something similar to the below line, rw should be in there.
/dev/mmcblk0p2 on / type ext4 (rw,noatime) [rootfs]
It turns out that I was the issue by only typing “satnogs-setup” and not “sudo satnogs-setup”
I really must not work so late in the night as I make stupid mistakes.
Thanks you for your help once again.
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I’ve removed the LNA now and set my settings to how they were previously as I’m not receiving anything with it connected.
Did you visual check if the LNA was activated ?
I set up the scripts to activate it on a pass but there is no visual indication on the LNA
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Can you check the functionality with and SDR program like GQRX, SDR++ or similar.
You should see a signal increase in the waterfall
I will run cubicSDR again and see what happens, when trying yesterday I was struggling to see anything on active frequencies. I thought the signal maybe to strong for the SDR
Can you share some details on the hardware and the settings you used to activate/use the LNA?
When using a RTL-SDR I use the following settings:
SATNOGS_SOAPY_RX_DEVICE="driver=rtlsdr"
SATNOGS_RX_SAMP_RATE="2.048e6"
SATNOGS_RF_GAIN="28"
SATNOGS_ANTENNA="RX"
SATNOGS_DEV_ARGS="biastee=true"
And this is with the combination of a RTL-SDR v3 and a nooelec wide band LNA
This is currently in use by station 431
This options is missing:
SATNOGS_DEV_ARGS="biastee=true"
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So the good news is that I have been able to confirm the LNA is switching on during a pass as it has a tinny green LED that lights up, bad news still no signal received.
https://network.satnogs.org/observations/10293570/
I have adjusted the RF gain down to 0 at the moment as it seems to be over powering the SDR it looked very strong in CubicSDR
Lacking waterfall, there might be some bad arguments to the flowgraph that is making it quit. Look at the logs.
Looking at the cubicsdr screenshot, I’d say it picks up broadcast FM very strong that messes with the VHF weater frequencies. If this is the case, putting a notch filter will make it better.
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Thanks for your help, I’ve ordered a filter and see if that works
While the FM interference is now blocked I’m still not able to get it to provide a waterfall of the signal.
For now I think I will remove the LNA and just leave the notch filter in position.
Yeah, often requires some experimentation to determine what works at ones location. Sweeping the spectrum to find strong transmitters is another good way to find what needs to be addressed.
And also find faulty or subpar modules.
Starting with a super simple setup and adding as few item as possible each iteration and checking the signals is a safe bet.
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