Trying to find the cause of this interference. I’ve ruled out lighting, and most power supplies / close by devices. Could it be the laptop? Any hints on adding filters to get this reduced. Thanks for any hints and tips James M0JFP (MX0MXO)
Hi James,
Can you also share more details on your setup and location, are there for example pager systems or broadcasting towers nearby.
What SDR, software, LNA, coax etc …
Jan | PE0SAT
Hi James, as Jan says, and if I am interpreting this right you are listening to the ISS voice repeater output, the selected signal looks like FM modulation, so with interference you mean the constant carriers to the left and the tight ?
73’
Ben
Hi Ben, yes you are right its the big red bands either side, the screen is zoomed in, but the bars are consistent over 70cm and 2 meters bands (egg beater antennas up high / chimney outside, decent ultraflex 7 cable 5 meters run to SDR / Radio
Thanks for any ideas, tonight I’ll try just battery laptop and power down anyting else around here, try and figure it out.
Best 73 and thank you Ben !
James M0JFP / MX0MXO
Please share a bit more info about the SDR and check the signals when the sun disappeared from nearby solar panel installations too.
As Ben mentioned,
Please more information on the SDR setup:
What SDR, sample rate, gain settings, AGC settings.
Do you use a LNA, if so what type, how is the LNA connected and is the DC connected.
The operating system you use and how the SDR is connected to the computer, laptop, or something else.
What software are you running and have you tried other version and do you have the same interference?
Basically share all the information that is part of the setup.
Jan | PE0SAT
Looks to me like qrm from nearby ethernet routers. They seem to put sprogs across the vhf and uhf spectrum every 60 - 70 kHz.
Good luck
Graham G3VZV
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I was testing “sky roof” as you guessed listening to ARISS / ISS FM voice repeater, on my windows laptop. However day to day, this is my Satnogs set up for m0jfp uhf SatNOGS Network - Ground Station M0JFP Staines Space and weather UHF and vhf SatNOGS Network - Observations , more details below:
OK I have a raspberry pi 3 and 4 rtl sdr blog 4 dongles, egg beater antennas, no LNA.
Pi boards are bare bone, rtl is inserted directly and the coax into that.
Just running the standard pi plug in psu / adapter.
Given the egg beaters, I was looking to maybe purchase 2 x preamps and get them fitted as close to the antenna (external) as possible. Do we think this would make significant improvement of more pull in the noise?
Best regards
James M0JFP (MX0MXO)