Compare gain before and after reflector adjustments
The reflector adjustments started around dec00
and finished in aug01. The improvement
in gain is shown in the plot. In Sep00 CTA21 was tracked doing position
switching using the lbn (1405Mhz), sbn(2380Mhz), and cband(5000Mhz) receivers.
In the fall of 2001 3C138 was tracked using calibration scans using lbw(1415Mhz),
sbn(2380Mhz), and cband(5000Mhz). The computed gains are plotted versus
za using different symbols for the two epochs. The sep00 meaurements did
not search for the peak of the source while the 2001 observations did.
Any pointing errors will decrease the gain of the earlier data. The lband
data was lbn in 2000 and lbw in 2001. The measured gain ratios for these
two receivers differs by about 14% at 1405. This is probably because the
cal values for lbn are off. I multiplied the lbn gains of 2000 by 1./.86
to make the comparison less biased. (Since this plot was a show and
tell for the visiting committe of course i corrected the lband gains to
the larger value!!!)