water in the waveguide, network analyzer measurements.



    The sband transmitter measures reflected power using directional couplers  at:

The waveguide path is:

aug15 problem   

    During the aug15 runs, there were a large number of reflected power faults. From the individual klystrons, and from the antenna reflected power. When we went to waster load (by switching the combiner), we never had a reflected power fault. This showed that the waveguide from the combiner back to each klystron was ok.
    It was then noticed that the antenna reflected power would mainly occur at low za.
    So the antenna reflected power at low za pointed to water in this section of waveguide.

On 17aug15 the waveguide along the rotary floor was opened and water was found inside it. This was cleaned out.

Later that evening the transmitter came up again and ran for about 20 minutes. It then started to have klystron reflected power faults again (but no antenna refllecte power faults).

measuring the waveguide with the network analyzer.

    The Rhode and schwartz network analyzer was used to measure S11 on the sband waveguide
The plots show the time domain reflectometer results (.ps) (.pdf)


Dana's notes on measuring S11 (,txt)

 processing: x101/150818/plottmd.pro 
<- page up