RF Distribution box

• The box resides in the LSC rack. It gets the demodulation signals from the frequency generation box and splits it into several outputs so that it can be used by the demodulation boards. The box also generates frequency multiples as 3xf1, 3xf2, 2xf1 and 2xf2 demod signals.

Latest Diagram

• The latest pdf file can be found here [https://nodus.ligo.caltech.edu:30889/svn/trunk/suresh/40m_RF_upgrade/RF_Distribution_Box.pdf 40m svn]

• The latest Omnigraffle file can be found here [https://nodus.ligo.caltech.edu:30889/svn/trunk/suresh/40m_RF_upgrade/OmniGraffle_files/RF_Distribution_Box.zip 40m svn]

• attachment:RFdistributionbox_1027_2011.png

Pictures

• This is how the Frequency Distribution Box looks like
• attachment:RFdist_2011_Oct_27.png

• Some more pictures are available in [https://picasaweb.google.com/foteee/ModificationOnRFDistributionBoxOct262011?authuser=0&authkey=Gv1sRgCIO18N6kgfiyKA&feat=directlink 40m Picasa]

References

• [1] Measurement of the output RF levels [http://nodus.ligo.caltech.edu:8080/40m/4342 40m elog #4342]

• [2] Measurement of the harmonic distortions [http://nodus.ligo.caltech.edu:8080/40m/4374 40m elog #4374]

• [3] Modification on the box [http://nodus.ligo.caltech.edu:8080/40m/5744 40m elog #5744]

BR

Some Thoughts in Early Days

40m Upgrade RF Distribution Box

• This box will serve to split the RF signal coming from the RF Modulation Generator into the signals to be fed to the demod boards.

• It will distribute both 11 and 55 MHz frequencies. It will also provide the 3f demod signals.
• The box will contain 2 8-way power splitters, 2 frequency triplers, 2 2-way power splitters.
• The box will have to be powered.

Plans

RF Distribution

• 1. Construction of Frequency Distribution Box
• exactly the same as for the frequency generation box
• 1. Demod board filter upgrade: installation of surface mount low pass/high pass filter
• 1. LSC rack routing