SDRplay Community Forum

Hello there.

I'm using my SDRPlay RSP1 on Windows 10. Must say that I'm a newbie.

Everytime I use SDRUno with my RSP1, I'm seeing a constant line on the waterfall's center, in every single frequency. Can't really figure out what the heck is that. Screenshot:



What is (or could) it be? Any ideas?

Hello,
The RSP uses a zero IF architecture and the spur you are seeing results from residual DC offset in the I/Q signal paths. This is sometimes referred to as a 'centre spike'. It is rarely a problem, but it is important to ensure that your VFO is offset from this spike as the DC offset correction algorithms will distort AM signals. If this small spur bothers you, you can select Low IF mode and the spur will not be present. However in Low IF mode, you will be limited to a maximum of 1.5 MHz.

Sincerely

SDRplay Tech_Support

Thanks for the explanation.