The Lynx was made by C & G Technology, c. 1976-78. There were also Bobcat and Wildcat models. "C" and "G" were Ray Crum and Jack Gifford (who later founded Tesoro).
These were great machines when they came out. They were discriminators that were hard to match but lacked in depth. I still wished I had one to play with.
C-Scope had their own version of 'off-resonance' detector at the same time. Far better than the normal discrimination of that, even this period but as you say lacking in depth.
You could also keep your eye out for the A.H. Pro models that worked on the same principle.
Another case where they threw the baby out with the bathwater. Modern componants would probably cope better with the drawbacks of the system but all development seemed to stop at the same time.
Excal 1000, Excal II, Sovereign GT, CZ-20, Tiger Shark, Tejon, GTI 1500, Surfmaster Pulse, CZ6a, DFX, AT PRO, Fisher 1235, Surf PI Pro, 1280-X, many more because I enjoy learning them. New Garrett Ca