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RTL-SDR displayed bandwidth.
Posted: Sun Jan 08, 2023 5:50 pm
by G4EWJ
I've finally acquired a Portsdown4 and I'm exploring its many wondrous features.
With an RTL-SDR, the displayed bandwidths seems to be 0.5MHz and 1MHz, rather than the 1MHz and 2MHz values shown on the menu and graph.
This is version 202301020 with a 7 inch screen.
Brian
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Re: RTL-SDR displayed bandwidth.
Posted: Sun Jan 08, 2023 7:37 pm
by G8GKQ
Hi Brian
Not sure how I missed this in testing - very embarassing!
I've reproduced the fault and will work on a fix.
Dave
Re: RTL-SDR displayed bandwidth.
Posted: Sun Jan 08, 2023 7:46 pm
by G4EWJ
You can't catch everything.
It's quite handy really. Can you leave it as a third option?
Brian
Re: RTL-SDR displayed bandwidth.
Posted: Sun Jan 08, 2023 7:54 pm
by G8GKQ
Hi Brian
I have identified the problem. I left a testing setting in the final build. I will fix it in the next Portsdown update, but if you want to correct it in the interim, open the file /home/pi/rpidatv/src/rtlsdrview/rtlsdrfft.c and uncomment line 84 and comment out line 85, so it looks like this:
Code: Select all
#define DEFAULT_SAMPLE_RATE 2048000
//#define DEFAULT_SAMPLE_RATE 1024000
then run the command
Code: Select all
/home/pi/rpidatv/scripts/utils/ubvr.sh
to compile the corrected version. Then restart the BandViewer.
I'll push a Portsdown 4 update to fix this asap.
Dave, G8GKQ
Re: RTL-SDR displayed bandwidth.
Posted: Sun Jan 08, 2023 7:56 pm
by G8GKQ
I'll work on the 500 kHz bandwidth option as a slower time task.
Dave
Re: RTL-SDR displayed bandwidth.
Posted: Sun Jan 08, 2023 8:08 pm
by G4EWJ
Thanks.
Brian
Re: RTL-SDR displayed bandwidth.
Posted: Mon Jan 09, 2023 12:33 pm
by G8GKQ
I have just released a Portsdown 4 update with a fix for this problem. Just update to the latest version if you want this fix.
I will work on implementing the 500 kHz span width selection in a future update.
Dave, G8GKQ
Re: RTL-SDR displayed bandwidth.
Posted: Mon Jan 09, 2023 3:05 pm
by radiogareth
Works for me, very handy for /P. The 50MHz of the Pluto and its frequency coverage really is an outstanding feature (too)!!
Thanks
Gareth
Re: RTL-SDR displayed bandwidth.
Posted: Wed Jan 11, 2023 9:11 pm
by G8GKQ
I have now released updates for both the Portsdown 4 and the Portsdown 2020 which include (corrected!) span widths of 500 kHz, 1 MHz and 2 MHz for the RTL-SDR BandViewer.
I have also added a very basic RTL-SDR BandViewer capability for those Portsdown 2020 users with Waveshare 3.5 inch screens. Please read the wiki entry here (and do a software update!) before trying to use it.
https://wiki.batc.org.uk/Portsdown_Band ... he_RTL-SDR
Dave G8GKQ
Re: RTL-SDR displayed bandwidth.
Posted: Thu Jan 12, 2023 1:07 pm
by G4EWJ
Is 202301100 the latest version for Portsdown4? I'm not seeing the 500kHz option on the RTL-SDR band viewer.
Brian