FreqShow

Software Release 201801012 introduced the FreqShow spectrum display program provided by Adafruit. This application, selected from Menu 3, enables you to display 2.4 MHz of the frequency spectrum as received by the RTL-SDR dongle.

Author's Information

Thanks to Tony DiCola for making this application available to the community through adafruit. The adafruit website has a lot of information about the application: https://learn.adafruit.com/freq-show-raspberry-pi-rtl-sdr-scanner/overview. Thanks also to John, GI7UGV for providing the install specifics for the Portsdown build.

Suggested Usage

The primary usage of the FreqShow application may be to check for interfering signals near expected DATV Transmissions. Here is an image of a weak 333KS transmission at 146.5 MHz.

The second usage of FreqShow could be to peak up on a carrier prior to attempting DATV reception. Here is an image of a carrier at the same output power as the weak 333Ks transmission above.

Changing the Default Settings

The start-up settings for FreqShow can be amended in the file /home/pi/FreqShow/model.py. Note that any changes that you make will be overwritten by future software updates. Settings can also be changed, for the current session only, by selecting the config button.