Background:

• This was to test the hf prior to the  15mar18 hf run.
• 180307 test showed tx 4 had large reflected power.
•  the next day up to 2 gallons of water was removed from the heliax line by the splice under the bowl.
• This was probably leakage from when the splice was under water after hurricane maria. (lago arecibo :).

What we did:

• The mesh was in the 5 MHz position (i assume..)
• we transmitted at 5.125 MHz rcp.
• Only 2 generators were available to provide power to the hf. the 430 tx was on commercial power.
• 430 tx, single beam -> gr. za started at 1.06 then moved to 3 deg
  
• gr -> usrp
• ch -> echotek [-5.5,5.5]
• we heard the waveguide arcing up on the platform.
  
• 10:10 bring up 430tx (approx)
  
• 11:00 rf off 430 tx.. we could hear arcing upstairs.
• 10:54 hf rf on.
• hftx 1-5 come up ok
• hftx 6 won't come up. filament timer is not timing out.. run with 5 tx till 14:05 when tx 6 comes up.
• 11:13 rf off
• 11:14 rf on for 30 secs then back off.
  
• 11:33 rf on
• 11:50 rf off
• 11:54 rf on
• 12:06 bring power up to  60*5 kw
• 13:00 start recording 1 sec spectra with interim cor.
  
• 13:06 raise power 65*5
  
• 14:05 start bringing up tx 6.
• 14:06 looks like tx1-5 rf switched off while 6 comes up
• 14:12 all tx back up
• 14:18  raise power.. shooting for 70kw*6
• 14:23  gen 3  trips with coolant over temp.. generators shut down.
• done.
  

HF output power

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

• Top: hf rf coupler output vs hour of day
• Each color is a different tx.
• the low blue level is when tx4 was disabled.
• middle: output power in KW
• bottom: synth drive amplitude (in dbf)
• The red line with noise it the total power from the gregorian receiver measured with the interim correlator
• This was started around 13:00
  

Generator power vs hf output.

    The data from the 2 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

GenPwr notes:

• generator 3 had a low pressure, then pre high temp warning.. (more info)
  

Summary:

• Tx 4 no longer had reflector power.. it worked ok after removing the water from the heliax.
• previously S11 measurements were done with the water in the heliax 4.
  
• The values measured did not show a problem. it would be interesting to re examine the data (if it was recorded).
• Tx 6 had trouble with the filament timer relay. It was fixed around 14:00.
  
• We had lots of arcing.
  
• we ran 350 KW using 5 transmitters.
• The low pressure warning on gen 3 occurred during this period.
• With 6*70KW gen 3 tripped with high coolant temp
• The generator mechanic cleaned the airflow for the motor radiator after this run.
  

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