Quote:
Originally Posted by tripelo
Looks like displays from three different STL-SDR units,
that is if the RTLSDR Scanner is running on one of the lower cost devices?
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That is correct. The last three images were:
1. RTL-SDR.COM V3 dongle with free open-source Scanner software from GitHub
2. SDRplay RSP1A SDR with SDRuno software
3. Airspy R2 SDR with Spectrum Spy software that is included with the SDR# (SDRsharp) software download
Quote:
When comparing the SDRplay and the Airspy,
noticed the noise spectrum on the lower frequency side of Channel 3 is different for each.
Specifically, the noise is increasing near lower edge of Ch3 for the SDRplay,
for the Airspy decreases a bit near lower edge of Ch 3.
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Yes; three factors account for that:
1. The noise floor is not constant on VHF, especially VHF-Low; the scans were done at different times
2. The RSP1A with the SDRuno software is limited to a useful bandwidth of about 8 MHz; each side falls off pretty fast. The Airspy R2 with the Spectrum Spy software has an extremely wide bandwidth for a scan only limited to the full bandwidth of the R2.
3. The bandwidth of the antenna
