DVBC frequency tables are in xml files in this folder: C:\Program Files (x86)\J River\Media Center 22\TV\DVBC\
There are four files there for Switzerland - Switzerland.interGGA-GGAPratteln-EBM.xml, Switzerland.sasag.xml, Switzerland.thurcom.xml, and Switzerland.UPC Cablecom.xml. One file per provider. The files contain the frequencies and other tuning parameters of channels for the given provider.
You can created an xml file yourself. Just copy one of the files, rename the copy Switzerland.localnet.xml, and then edit it in Notepad.
The file should contain entries like the following:
<Transponder Frequency="330000" Modulation="256QAM" SymbolRate="6900" />