Shims were used to move the wideband horn
closer/farther from the secondary to search for the focal
point. The shims were 1" thick.
more info:
date |
#shims/distance to secondary |
freq |
230529 |
2, 22.6" |
xb |
230531 |
1, 23.6" |
xb |
230601 |
0, 24.6" |
xb |
230602 |
2, 22.6" |
xb |
230603 |
2, 22.6" |
xb |
230604 |
2,22.6" |
3ghz |
230607 |
3, 21.6" |
xb |
230608 |
3,21.6" |
3ghz |
230609 |
4,20.6" |
3ghz |
230610 |
4, 20.6" |
xb |
230611 |
4, 20.6" |
xb |
230612 |
4, 20.6" |
xb |
230613 |
4,20.6" |
3ghz |
230614 |
5,19.6" |
xb |
230615 |
5,19.6" |
3ghz |
230616 |
5,19.6 |
xb |
230617 |
5,19.6 |
xb |
230619 |
4,20.6" |
xb |
Plots were made for each 172MHz freq band.
Each plot has 8 pages
freq (MHz) |
all shims vs elevation |
all shims vs azimuth |
2-5" shims vs elevation |
2-5" shims vs azimuth |
8223 |
(.ps) (.pdf) |
(.ps)
(.pdf) |
(.ps)
(.pdf) |
(.ps)
(.pdf) |
8363 |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
8505 |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
8647 |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
8789 |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
8931 |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
9073 |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
(.ps) (.pdf) |
We observed some shim positions on multiple days. The
above plots show that there can be a lot of variation in tsys
on different days (from the weather).
To try and exclude variations caused by weather:
The table below replots the data using 3C405 and M87 , shim
spacings 2" to 5" and only using the "Best day" for
those shim spacings
measured multiple times.
freq (MHz) | 2-5" shims vs elevation |
2-5" shims vs azimuth |
8223 |
(.ps) (.pdf) | (.ps) (.pdf) |
8363 |
(.ps) (.pdf) | (.ps) (.pdf) |
8505 |
(.ps) (.pdf) | (.ps) (.pdf) |
8647 |
(.ps) (.pdf) | (.ps) (.pdf) |
8789 |
(.ps) (.pdf) | (.ps) (.pdf) |
8931 |
(.ps) (.pdf) | (.ps) (.pdf) |
9073 |
(.ps) (.pdf) | (.ps) (.pdf) |
XBand Notes:
processing:
freq |
all shims vs elevation |
all shims vs azimuth |
2846 | (.ps) (.pdf) | (.ps) (.pdf) |
2988 |
(.ps) (.pdf) | (.ps) (.pdf) |
3130 |
(.ps) (.pdf) | (.ps) (.pdf) |
3272 |
(.ps) (.pdf) | (.ps) (.pdf) |
3414 |
(.ps) (.pdf) | (.ps) (.pdf) |
Processing: x101/230604,09,13 / wb3cross.pro
x101/12meter/comm/shimproc_wb3.pro