S-Level monitoring and plotting


#1

A friend of mine suggested this a couple of days ago, and I thought it would be a great idea: a Wizkers:Radio mode that is a S-Level monitor.

The idea is to follow band noise over long periods of time to see how it changes across the day. It can be a good tool to understand how the band behaves, as well as for tracking interference that occurs every once in a while and understand possible patterns… the possibilities are pretty much endless!

This is a quick proof of concept for the tool. If there is any interest for it, I will add it as a new “Instrument” in the next release of Wizkers:Radio once I have a version that’s more useful. The release version will also let you record those graphs and replay them - possibly even overlay recordings to live graphs to understand how conditions at your QTH evolve, etc…

Feedback ?


#2

Looks nice! Since you asked for comments, I have a few thoughts:

  • Ideally, the graph would have a title saying what frequency is being measured. Alternatively, maybe have a colored line and a key in the graph to show what frequency noise data point is and if you QSY the radio, the graph will then show new color for the data point
  • You need to label what is the Y-axis… I would assume this is S-units? Maybe they are DB?
  • Is it possible to write the timestamp text vertically so they don’t smoosh together?
  • If you’re gathering data for say multiple days, is it possible to “zoom out” and better see trends? This is the real value to spot say RF interference from your neighbor’s plasma TV when they watch a little TV say from 8-11pm every night!

Btw, my Ft857+Hamlib solution would scan and report the noise floor on multiple frequencies so I could better understand the scope of the noise. This helped a bit but the FAR better solution was to use a wideband SDR witha waterfall (Gqrx). Once I could see 2.4Mhz ($10 RTL dongle) or 10Mhz with an AirSpy v2, it was much easier to understand the breadth, type, and stability (drifting?), and persistence of the interference.

–David


#3

Thanks @ki6zhd for the comments! Good points. Below is a slightly better UI - I will indeed show the radio frequency on the currently blank right side, along with the controls. Zoom support will be nice too, this is a core feature on the platform I have been meaning to add for a long time…

The graph below is W6WX on 14.1 which is the only 20m beacon I can hear really clearly. I’m tempted to write an automated beacon monitor, but afraid I’ll wear out the KX3 with constant band switching and associated relay clicking…