Radio frequency performance of DSS 14 64-m antenna at X-band using a dual hybrid mode feed

The 64 meter antenna X-band system at DSS 14 was evaluated to determine the performance with the new dual hybrid mode feed. The peak system efficiency increased from 42.0 to 45.6 percent resulting in a 0.36 dB increase in antenna gain. The new measured gain is 71.6 dB. Antenna pointing, beamwidth, optimum subreflector focusing, and operating system temperature were unchanged from the previous feed. Some evidence of antenna aging is apparent (from the 1973 measurements reported earlier) both in peak gain and in the pointing angle at which the peak occurs.