The resolution on the waterfall screen is fixed by the bandwidth mode, so if it is set to 156kHz, the raw BW is 192kHz and there are 16384 bins so you get 11.7Hz/bin.  In the IF, you get less bandwidth and higher resolution, so 48kHz/16384 = 2.9Hz.  For any higher res, I just use Spectrum Lab at audio, with FFT length 262144 at 48k sample rate, even without further decimation, that gets you to 250mHz or so.  I guess you could output a 48kHz IF from a VRX into Spectrum Lab via a VAC and use it on a wider span than AF.  Not tried it though.

Neil G4DBN

On 17/01/2020 10:20, John Fell wrote:

Neil,

Thanks for the info to increase available frequency span in ADVANCED setup .

I initially could not find where it was but the DEVICE config is a drop down , with selectable options .

This answers a question I was about to pose : can you change the default 11.7HZ/point FFT res ?

The 192kHZ span in default Config option is the one with 11.7HZ that I have used so far  . 

Is it possible to have 6HZ or even lower FFT values ( with reduced span)  ?

View/Reply Online (#16525) | Reply To Group | Reply To Sender | Mute This Topic | New Topic
Mute #elad | Mute #fdm-duo | Mute #fdm-s2
Your Subscription | Contact Group Owner | Unsubscribe [neil@...]