Missile launch detection (how does it work)

i was reading about cold war aircraft and they had the ability to detect if a SAM site had a launch.

how was this detected back then with 60s/70s technology? was the detection done on ground and the info relayed to the aircraft or was it actually detected from the plane? could these systems predict the target for these launch or just the launch itself?

Please i'm not looking for answers like "Radar" or "EWS" (detection for ICBMs). i am looking for system names an info, either land or craft based.

thank you for your time

Early SAMs had 2 radar systems. A "Search Radar" that covered the whole sky and searched for enemy aircraft and a "Guidance or Tracking Radar" that was narrow beam and locked on the target. Guidance was "on" only when tracking a target and pointed only at the target, the missile "rode the beam" to the Target. Search continued to search the sky for additional targets. When the Guidance lit up, the pilot got a warning that he was being tracked.

http://ed-thelen.org/ifc_track.html

http://www.answers.com/topic/search-rada…

http://en.wikipedia.org/wiki/List_of_rad…

http://en.wikipedia.org/wiki/MIM-23_Hawk

Search Radar also had the IFF job (Identification Friend or Foe). The aircraft had a Transponder that when interrogated by the Search Radar replied basically "Don't shoot at me you idiot! I'm on your side."