This short video shows the transmission of the radio signals in real time, using a spectrum analyzer.
This is a waterfall view, in which the vertical axis is in decibels (dBm), the horizontal axis is the frequency, in Megahertz, and elapsed time is into the screen.
The colors indicate the strength of each signal, from blue for the weakest, through the color spectrum to red for the strongest. The time when the recording was made is shown along the time axis on the right hand side.
You can run and pause the video by clicking on the button at the left hand end of the progress bar. You can also click at any position on the progress bar when the video is paused to view the state at that point in time. You can also click on the progress bar when the video is running to restart it from that point.
Although the shapes of the pulses are distorted slightly by limitations imposed by the spectrum analyzer, they are a good representation of the activity. Each large pulse is a packet of data being set over one of the networks. The lower level pulses are background radio noise from other sources.
The transmissions for the first ZigBee channel, which is 12, can be seen as a line of pulses moving into the screen at 2410 MHz. Similarly, ZigBee channel 14 can be seen at 2420 MHz.
The Raspberry Pi WiFi transmissions, which are on WiFi channel 6, are centered at 2437 MHz, and are spread from 2427 MHz to 2447 MHz. The home WiFi transmissions are similarly on channel 11, which is centered at 2462 MHz, and spread from 2457 MHz to 2467 Mhz.
There are occasionally strong pulses at about 2480 MHz, which are from another source.