A diagram like Fig. 3 obviously ... One of the methods involved a special hard- wired dispersion remover [IS], while the other surveys were done with digital computers, either off-line  or on-line , . Taylor  ... L125-L130, June 1969.
|Title||:||Instrumentation and techniques for radio astronomy|
|Author||:||Paul F. Goldsmith, IEEE Microwave Theory and Techniques Society|
|Publisher||:||IEEE - 1988|