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Table of Contents
Feed Testing
June 05, 2018 - received the mini circuits attenuator and 8 port RF switch. Two of each.
Note: That is a quarter coin in the center for size reference.
Feed Measurements - May 09, 2018
Various feed measurements using the spectrum analyzer. Using feed 4jx. May 09, 2018
In all these pictures please pay attention to the dB and bandwidth scaling, these are not the same in all pictures.
Removed the RFCB filter
Turns out that without the filter there is 600MHz bandwidth to play with.
With 200MHz filter, pointed at az 330, el 30:
Without 200MHz filter:
Pic of the filters, and the 200MHz filter bypassed for feed 4jx:
For reference, here is the original RFCB drawing I found:
CasA
CasA at 1420, looks like it always does:
W3OH
Did not see the bump at 1665MHz.
1613.9MHz:
1667.348MHz:
1718.74MHz
8MHz comb RFI
Using the spectrum analyzer I discovered there is a spike every 8MHz from 1000 to 2016MHz. ONLY on the new feeds. No matter where i pointed. The old feeds do not have this spike.
On feed 3Lx it was very strong, this is a 120MHz badwidth shot:
