Pick the network a television show originally showed on. In the case of a television show that began on one network, and was picked up by a second one, we're looking for the first network. All shows began during the 1970s.
1. "Welcome Back, Kotter"
2. The Dukes of Hazzard
3. Salvage 1
4. The Misadventures of Sheriff Lobo
8. Kolchak: The Night Stalker