For special purposes (like broadcast listening, hunting for "DX" utility stations), the main frequency scale may show the frequencies of 'points of interest'.
(VLF spectrum/spectrogram with 'Radio Station' display)
The frequency list can be loaded from a textfile; the format (and where to find suitable databases) is described in frequencies/readme_freqlist.txt .
Loading and displaying a frequency list
Besides the EU NDB list (by courtesy of Sean, G4UCJ), there is only a small 'default' list contained in the Spectrum Lab installation archive. To use a different list (for example the EiBi shortwave broadcaster list), enter SpecLab's main menu and select Options ... System Settings ... Filenames and Directories ... Radio Station List .
Doubleclick into the edit field to open a fileselector. Then select the file type (SL can load frequency lists from textfiles or semicolon-separated "csv" files). Multiple files can be selected for loading by holding the CTRL key down in the file selector box. If multiple files were selected, their names will be separated by commas in the edit field on SL's Filenames tab:
(screenshot of the 'Filenames' tab)
The colour of the radio station display (for the spectrum graph and the main
frequency scale) can be modified through the main menu, too: Select
Options ... Display Colors and Fonts ... Radio
Station Frequency Markers .
See also: Spectrum Lab's main index , programmable frequency markers , spectrum displays , main frequency scale , VLF receiver , README from the 'frequency list' folder .