span adjustment on SDRuno 1.12

[W0IVJ]

I am using an RSP1 with SDRuno 1.12. My spectrum span seems to be fixed at 64 kHz. How do I adjust it?
Thanks, Tom

[g1hbe]

Hi Tom
That's a very narrow span for the RSP1 and Uno, unless you have somehow got into 'zoom' mode. First of all, set the Sample Rate to 2 MHz and the Decimation to 1 (both these settings are in the small MAIN window). This should give a visible span of about 2 MHz. If it is much narrower than this, you must be zoomed in. To zoom out, click the LH ZOOM button just below the waterfall display. Keep clicking until the display won't un-zoom any further. Hope I've understood your post correctly.

[W0IVJ]

Thanks for the quick reply, Andy. It looks as if under SDRuno 1.12 I can only get a maximum of 1024 kHz with the SR set to 8.192 and DEC set to 4. I downloaded HDSDR 2.75 Beta3 and I can no longer set the LO above the operating frequency and the maximum span is 2 MHz. Using HDSDR 2.70 with RDS1, I can set the LO to be above the operating frequency, which is preferable from a mixing spur standpoint, and I can get the full panadapter span. What I dislike about HDSDR is that the S-meter and the panadapter disagree by about 10 dB. SDRuno does not have that problem.

My real question is how do I get the the full span of 10 MHz using RSP2 and SDRuno 1.12 ?
Thanks, Tom W0IVJ

[W0IVJ]

Hi Andy,
I think I figured it out. To get full panadapter span, you have to go to the zero-IF mode. Is this correct?
Tom W0IVJ

[g1hbe]

Yes, the full range of spans is only available when in 'zero IF' mode. But I don't think I've ever seen a 64k span in any mode, I'll have to have a look later. Is your setup behaving in a sensible manner now?

[W0IVJ]

Hi Andy,
Yes, everything seems normal except for one thing...when I set the SR to a bandwidth of say 4 MHz and and the decimation to say 2, I would expect a span of 2 MHz, but I get 1 MHz. This is consistent with all combinations of span and decimation. The span seems to be less by a factor of 2. This means that the maximum span is 5 MHz instead of 10 MHz.
Tom

[W0IVJ]

Hi Andy,
With SR set to 2 MHz, DEC set to 8, and full zoom, the Span is 7.8 kHz. That is the smallest span I am able to get.
Tom