Here is the schedule from PBS affiliate KPBS-TV in San Diego, CA for Saturday December 7, 1974
NOTE: KPBS is during its Membership Awareness Week(December 6 through December 15, 1974) so I don't know if the station had another membership pledge campaign either August or September 1974 before the December Awareness Week.
7:00 AM Sesame Street
8:00 AM The Electric Company
8:30 AM Zoom
9:00 AM Carrascolendas
9:30 AM Villa Alegre
10:00 AM Sesame Street
11:00 AM The Electric Company
11:30 AM Walsh's Animals
12:00 PM Zee Cooking School
12:30 PM Mr. Wizard
1:00 PM NOVA
2:00 PM Soundstage
3:00 PM The Life of Leonardo DaVinci
4:00 PM Behind the Lines
4:30 PM What Now, America?
5:00 PM The Way it Was
5:30 PM Black Perspective On the News
6:00 PM Washington Week in Review
6:30 PM Wall Street Week
7:00 PM KPBS Membership Appeal
7:05 PM Speaking Freely
8:05 PM KPBS Membership Appeal
8:10 PM Evening at Symphony
9:10 PM KPBS Membership Appeal
9:20 PM Ragtime (Host: Max Morath)
10:20 PM KPBS Membership Appeal
10:30 PM Soul
11:30 PM Sign-Off
NOTE: KPBS is during its Membership Awareness Week(December 6 through December 15, 1974) so I don't know if the station had another membership pledge campaign either August or September 1974 before the December Awareness Week.
7:00 AM Sesame Street
8:00 AM The Electric Company
8:30 AM Zoom
9:00 AM Carrascolendas
9:30 AM Villa Alegre
10:00 AM Sesame Street
11:00 AM The Electric Company
11:30 AM Walsh's Animals
12:00 PM Zee Cooking School
12:30 PM Mr. Wizard
1:00 PM NOVA
2:00 PM Soundstage
3:00 PM The Life of Leonardo DaVinci
4:00 PM Behind the Lines
4:30 PM What Now, America?
5:00 PM The Way it Was
5:30 PM Black Perspective On the News
6:00 PM Washington Week in Review
6:30 PM Wall Street Week
7:00 PM KPBS Membership Appeal
7:05 PM Speaking Freely
8:05 PM KPBS Membership Appeal
8:10 PM Evening at Symphony
9:10 PM KPBS Membership Appeal
9:20 PM Ragtime (Host: Max Morath)
10:20 PM KPBS Membership Appeal
10:30 PM Soul
11:30 PM Sign-Off