Suggestions:
1. Normally, the radar is not used for any specialized direction finding, i.e. "directional radar" could possibly be referring to Direction-Finding (DF) system.
2. Visit
for more info
3. Contact:
3a. ESL, Sunnyvale, CA, USA for Trailblazer, which is a local or remotely controlled tactical ground based communication intecept and DF system
3b. Technology for Communications International, Sunnyvale, CA, USA for AN/TDR-27 HF DF System
etc.