Network/mux/service charset fails with ATSC PSIP EPG grabber
EPG data from the PSIP ATSC EPG grabber is being incorrectly processed as UTF-8 - per specification, ATSC EPG data is sent OTA as ISO-8859-1. Setting the character set in DVB Inputs > Networks, Muxes, and Services to ISO-8859-1 has no effect. EPG data retrieved through the HTTP API is sent as UTF-8 JSON but contains invalid ISO-8859-1 characters. EPG data displayed within the Tvheadend UI is also displayed with invalid characters. Per the ATSC specification:
C.2 CHARACTER SET DEFINITION This compression method supports the full ISO/IEC 8859-1  (Latin-1) character set, although only characters in the ASCII range (character codes 1 to 127) can be compressed.
Attached is a sample of EPG data retrieved through the HTTP API that Tvheadend sent as UTF-8 but contains ISO-8859-1 characters, as well as a UI screenshot with the invalid decoding. Issue is seen on both stable 4.2.6-15~g88ae077 and the unstable 4.3-1288~g66d6161 - let me know if I can provide any further info, thanks!