I use PLUTO with SDR Console V3.0.38 as a PAN adapter for my 2 meter contests. There is always a DC in ther middle of the screen and also mirror signals are not suprest as I would expect.
for my Funcube dongle I have a special tool , where I can eliminate DC and mirror signal, but for PLUTO I did not found anthing like that. Maybe the automatic compensation is switched off, but I do not know, how to switch it on. Please help.
Jirka OK1MWW
Elimination of DC and Mirror signals
Re: Elimination of DC and Mirror signals
With SDRC that pip in the center is most often associated with poor and ineffective gain control settings. I usually run with manual RX gain set to 32 dB with visual gain set to about -3 dB. The latter gives me a reasonably accurate level display. The former brings up incoming noise to a level that masks that central pip.
In general, the central pip comes from self-conversion of the local oscillator within the front end. This can be mitigated. And SDRC does it about as well as most tools. It is a mathematically inevitable feature of the way most systems work.
{^_^}
In general, the central pip comes from self-conversion of the local oscillator within the front end. This can be mitigated. And SDRC does it about as well as most tools. It is a mathematically inevitable feature of the way most systems work.
{^_^}
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Re: Elimination of DC and Mirror signals
Hi,Jirka OK1MWW wrote: ↑Sun Jul 25, 2021 2:32 pm I use PLUTO with SDR Console V3.0.38 as a PAN adapter for my 2 meter contests. There is always a DC in ther middle of the screen and also mirror signals are not suprest as I would expect.
for my Funcube dongle I have a special tool , where I can eliminate DC and mirror signal, but for PLUTO I did not found anthing like that. Maybe the automatic compensation is switched off, but I do not know, how to switch it on. Please help.
Jirka OK1MWW
Screenshot please and show the Radio pane in the receive DSP - this way I can see the gains. The spur and mirror is due to IQ and can usually be corrected.
I've attached a screenshot for QO-100 where Pluto is actually receiving at the LNB frequency - note the gain settings.
At 144MHz Pluto is working outside the spec. I have no spur when receiving on 144MHz.