2 - WHP-21 (CBS) Harrisburg*
3 - WGAL-8 (NBC) Lancaster*
4 - WTPA-27 (ABC) Harrisburg
5 - PCI-5 (Local)
6 - WITF-33 (PBS) Hershey*
7 - WPHL-17 (Independent) Philadelphia
8 - WLYH-15 (CBS) Lebanon
9 - WOR-9 (Independent) New York City
10 - WTAF-29 (Independent) Philadelphia
11 - WPIX-11 (Independent) New York City
12 - WSBA-43 (CBS) York
13 - WKBS-48 (Independent) Philadelphia
* denotes that channel is still at that position today
Changes over the years for the "core 12":
1979 - PCI-5 is bounced for WGCB-49, a religious independent station in Red Lion
1983 - WKBS goes off the air; local origination (electronic bulletin board) moves to channel 8, and WLYH moves to 13
1989 - WPHL and WPMT (formerly WSBA) switch positions with WPHL going to 12 and WPMT going to 7
1991 - WPMT and WGCB switch positions with WPMT going to 5 and WGCB going to 7; WTXF (formerly WTAF) bounced to make room for TBS
1993 - WOR-9 bounced for AMC; Capital Region Access TV moves to 9; AMC goes to 25
1999 - WPIX moves from 11 to 10; TBS moves to 50; QVC moves to 11
2004 - WHTM (formerly WTPA) moves to channel 9 due to interference from WHP's digital channel on VHF 4
2007: WPIX dropped from lineup
2018: WPHL dropped from lineup
3 - WGAL-8 (NBC) Lancaster*
4 - WTPA-27 (ABC) Harrisburg
5 - PCI-5 (Local)
6 - WITF-33 (PBS) Hershey*
7 - WPHL-17 (Independent) Philadelphia
8 - WLYH-15 (CBS) Lebanon
9 - WOR-9 (Independent) New York City
10 - WTAF-29 (Independent) Philadelphia
11 - WPIX-11 (Independent) New York City
12 - WSBA-43 (CBS) York
13 - WKBS-48 (Independent) Philadelphia
* denotes that channel is still at that position today
Changes over the years for the "core 12":
1979 - PCI-5 is bounced for WGCB-49, a religious independent station in Red Lion
1983 - WKBS goes off the air; local origination (electronic bulletin board) moves to channel 8, and WLYH moves to 13
1989 - WPHL and WPMT (formerly WSBA) switch positions with WPHL going to 12 and WPMT going to 7
1991 - WPMT and WGCB switch positions with WPMT going to 5 and WGCB going to 7; WTXF (formerly WTAF) bounced to make room for TBS
1993 - WOR-9 bounced for AMC; Capital Region Access TV moves to 9; AMC goes to 25
1999 - WPIX moves from 11 to 10; TBS moves to 50; QVC moves to 11
2004 - WHTM (formerly WTPA) moves to channel 9 due to interference from WHP's digital channel on VHF 4
2007: WPIX dropped from lineup
2018: WPHL dropped from lineup