Modified Reference Cavity Measurements at CERN

The signal was excited using a weakly coupled probe and measured from the output feedthroughs. We only had one spacer and we put this on feedthrough 2. The spacings between the end of the feedthrough and the wall of the reentrant part of the cavity were therefore:

Feedthrough Spacing/mmSorted ascending
1 0.0035
2 0.0080 (nominal)

Port 1 of the VNA was connected to the antenna while port 2 was connected to feedthrough 1. Feedthrough 2 was terminated with a matched load (left) and short circuited (right).

port1wload_a.png port_1wshort.png

Port 2 was connected to feedthrough 2. Feedthrough 1 was terminated (left) and short circuited (right).

port2wload.png port2wshort.png

The measured quality factors were:

Feedthrough QL QL+short
1 76 116
2 73 214

Edit | Attach | Watch | Print version | History: r3 < r2 < r1 | Backlinks | Raw View | Raw edit | More topic actions...

Physics WebpagesRHUL WebpagesCampus Connect • Royal Holloway, University of London, Egham, Surrey TW20 0EX; Tel/Fax +44 (0)1784 434455/437520

Topic revision: r1 - 16 Apr 2012 - FrancisCullinan

 
  • Edit
  • Attach
This site is powered by the TWiki collaboration platform Powered by PerlCopyright © 2008-2022 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding RHUL Physics Department TWiki? Send feedback