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BOX Calibrations

This is a list of steps for a box calibration in a LERA MKII

First make abc.cal.hdr en bvi where abc is the site name and add the information required. Easier to do copying abc.hdr file and modify accordingly.

This is an example of a abc.cal.hdr file for kak site

kak FMCALI FREQUENZ 27.300MHZ YEAR 2012 RANGE: 0.6000 KM,TRUENORTH:310 GRAD,RATE:0.209715S,NRRANGES: 80 0000000 LAENGE:157-51-30 WBREITE: 21-17-30 N MT: 1280 PWR: 4095 ANT: 8 MD:031 OFFSET:0.2 RXOFFSET: 124076836SS 0.000000 calibration 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000 0000000

1. use a calibration box and connect cables 1-8 or 1-16 in the respective RX
2. be careful about signal levels. Input to receivers should not exceed -50 dBm. DDS TX output is +18 dBm. Calibration box is -50 dB. Thus an attenuator of at least -20 dB is needed between DDS and calibration box. If using the output of the TX, use the "FWD" output which is -40 dB down from the TX output, not the TX output itself, and use the rotary attenuator to -9 dB.
3. check crontab -e on the dtacq to detect times of acquisitions, when an acquisition is finished prepare DDS. In terminal type

screen /dev/ttyUSB0 19200 now you are in the DDS interface), write the following commands

 $ QUE (If OK then means the DDS is answering)
 $ Fd 0.000000000000

1. Connect BNC attenuator in DDS (have speakers connected, chirping will stop and replaced by 80Hz hum). Next acquisition will be the calibration file, check time of last acquisition before connecting DDS.
2. After acquistion is done open a NEW terminal and type: cd data/abc where abc is site name
3. Find the last .dta file and copy it (this is supposed to be the calibrated file) cd ~/wera_import/ do_process_CAL.sh* paste_here_dtafile

this shell script will call the dtacq2wera.m file and perform the WERA to LERA conversion and create a .CAL file

1. After the shell script is done in the same terminal window write:

       plotlsq here_goes_CALfile

This will create the calibration with the WERA/GURGEL algorithm and create a file date_abc.CAL.amphase where date is the current date and abc is the site name

1. Move the recently created .CAL and .amphase files into the calibration directory:

      cd data/kok/calib/ (if there is not calib directory create one)
      mv ../here_goes_CAL.amphase_file .
      mv ../here_goes_CAL.file .

1. Make a symbolic link from the calibration.amphase file into the calibration.wera(this is the file that the algorithm will use)

      cd ~/etc/
      ln -s ~/data/acq164_XX/calib/here_goes_CAL.amphase_file calibration.wera

Check that the calibration.wera file does not have 0 and 1 anymore, it has the data created from the plotlsq algorithm

1. Disconnect calibration Box and remove DDS attenuator. Close all terminal windows, DDS window you can kill by CTRL A K