Background:

• This was to the first hf test with the 430MHz  tx since the mar18 campaign.
  

What we did:

• The mesh was in the 5 MHz position
  
• we transmitted at 5.125 MHz rcp.
• 430 tx, single beam -> gr. za at za=2.
  
• gr -> usrp
• ch -> echotek [5.5,9.5]]
• we heard the waveguide arcing up on the platform.
  
• 11:40  bring up the hf  tx.
• 11:50 trouble with tx5  in hv fault (update.. was a broken resistor).
• 12:06  5 tx at 60 kw each..
• 12:15  lots of arcing
• 12:36  turn off 1 tx at a time to see who it was.. then try 2 at a time.
• not obvious which tx (update. had a load cell cable arcing (burnt) after the run)
• 12:48 start to bring tx 5  back up.
• 13:00  60KW each of 6 tx.. arcing is less.
• 13:15  70 Kw each tx
• 13:20  cycle mode 1 sec on , 9 sec off.
• 13:35  cycle mode 2 sec on , 8 sec off.
• 13:49  cycle mode off. raise power to 75 KW each tx
  
• 13:56  cycle mode 2on 8 off
• 13:57 cycle mode off,
  
• 13:57 cycle mode 5 sec on, 5 sec off
• 14:01 stop cycle mode , raise power to 85 KW each Tx
• 14:12 cycle mode 2 on , 8 off
• 14:24 stop cycle mode
  
• 14:30 done
  

HF output power

Plots showing hf tx drive and output power (.ps) (.pdf)

• page 1:
• Top: hf rf coupler output vs hour of day
• Each color is a different tx.
• the low purple level is when tx5 was offline.
• The rapid changes in power are during cycle modes.
  
• middle: output power in KW
• bottom: synth drive amplitude (in dbf)
• page 2: hf drive power vs hf output power
• the output power (in KW) vs input drive power (in dbf) is plotted for each tx.
• values that lie below the trend, occur when an rf off occurs during a spectrum analyzer power average. cycle mode points have been removed.
  
• 
  

• dbf Drive for 85 KW output

  tx	dbf drive
  1	-4
  2	-8
  3	-6
  4	-9
  5	-2
  6	-6

  
  
• The average drive power for 85KW is -5 dbf.
  
• tx5 needs 3db more drive
• tx4 needs 4db less drive power.
  

Generator power vs hf output.

    The data from the 3 running generators was used to measure how much generator power was needed to drive the 5 then 6 hf transmitters.

Generator output power vs hf output power (.ps) (.pdf)

• Top: generator output power vs time.
• middle: total rf output from 5 then 6  hf tx
• bottom: gen power vs hftx output power

Plasma line movies

• Plasma line movies were made using the echotek and the usrp data. They had 10 sec integrations.
  
• A higher resolution movie was made with the usrp data. It blows up the freq and range showing the f-reqion line. The time resolution is still 10 seconds.
• Link to the movies
  

Summary:

• Tx  had trouble in the hv fault. The problem was found to be a broken resistor (it was replaced).
• For the first part of the test we had lots of arcing.
• after the experiment the loadcell cable was found to be burned. It had been disconnected and left lying on the td yoke (it will now be removed). This may have caused the arcing.
• we ran cycle modes of 1,9   2,8 and 5,5   at up to 55 KW/tx (510 KW total)
• tx 5 required 3db more drive power than the average value. It was at close to the drive limit.

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