My problem isn't the radio navigation, it's the other navigation gizmos in the -100 and -200 that look daunting. I looked at the manual, but my confidence level was lower than the perceived instructional value and I have backed away from this airplane. So VOR etc. I get. What's up with those other things? It's not the Omega Nav System, is it? I used to know how the 707 works, but have totally forgotten that stuff. It was another one with a unique and unusual nav system.