Introduction:

Testing sequence:

• Data was recorded from the ch receiver using the interim correlator
• the telescope started at az=285 deg. ch=8.8344 . the ch was later moved to za=0.
  
• We started with the array phased for left hand polarization (dana's convention)
• Each tx was brought up to full power and then back down individually
• We then slowly brought all of the transmitters up together to full power.
• The carriage was moved from stow (8.8 deg) down to za=0.
  
• This was to check for changes in signal strength into the ch receiver.
• We did some rf cycling tests:
• 4sec on, 4 sec off, 1 sec on, 2 sec off,
  
• .5 sec on, .5 sec off (gui crashed)
• .2 sec on .8 sec off (gui crashed)
• 1 sec on,1 sec off
• We then switched to right hand polarization phasing and did more rf cycling tests.

rf synth levels and totpwr from ch receiver.

     The log file from the gui driving the rfsynth was input and plotted  vs hour of day.  The  plots contain:

• amplitude (db below full scale). Each tx in has a separate color.
  
• the phasing used
  
• The total power (computed from the 25 Mhz,, 1 sec interim correlator dumps) was over plotted (db above Tsys .. with an offset for display)
  
• The dashed green line shows when the rf was cycled on and off.

• 12.1 to 16.1 hrs (.ps) (.pdf)  entire run
• Top has synth drive, rfon/off, and ch total power (in red)
• bottom: tx phase. You can see the left to right pol change at 15.95 hours.
• blowup of particular events (.ps) (.pdf)
  
• page 1: 12.7 to 13.65  bring each tx up and then back down.
• the ch power increased around 13.1 with tx2 running
• page 2: 13.66 to 14.1  bring up the 6 tx together.
• page 3: 15.07 to 15.114 move ch from 8.8344 to 0 deg za.
• 15.08 ch data jumped up at za=7.68
• 15.098 spike at za=5.289
• these jumps had the total power increasing 20db above the regular system temperature.
  
• page 4: 15.273 to 15.296  cycling 4sec on , 4 sec off (drive level 5 db below full power)
  
• page 5: 15.33 to 15.377    cycling 4 sec on , 4 sec off (drive level 2 db below full power)
• page 6: 15.38 to 15.4        cycling 1 sec on ,2 sec off (drive level 2db below full power)
• page 7: 15.44 to 15.46      cycling 4 sec on , 4 sec off. full drive power
• you see week glitches correlated with the on state.
• page 8: 15.461 to 15. 496 cycling 1sec on , 2 sec off. full drive power
  
• glitches at the cycle rate.
• page 9: 15.497 to 15.517  cycling 1 sec on , 1 sec off. full drive power.
• glitches at cycle rate (but tp sampling is only 1 hz).

Linearity: drive input to rf output

    The plot shows the rf drive (in dbf) vs the rf output power (dbm from coupler) (.ps) (.pdf)

• each tx is plotted with a different color.
• The transmitters were on antenna.
• The diagonal dotted lines have a slope of 1.

tx meter values recorded.

tube monitor ports  for tx 5 on scope.

• tx5 had lower output for than the other transmitters.
  
• the front panel monitor ports were recorded on compared to the values measured on 151021.
• The comparison showed that the driver stage had 9db less gain on 151029.
• see tube stage outputs for 151029
• for 151029 measurement:
• i switched the scope from 100K to 1e6 point scope buffers
• channel 1 (broadband output) was set to 5volt scale/div with 1 meg termination
• The 50 ohm termination only allows for 1v/div max
• 
  

  date	ipa output dbm (scope port)	driver output dbm  (scope port)
  151021	-.16	-5.73
  151029	7.74	-6.76
  29octvalue	7.9 db higer	1db lower

• So the driver has 9db less gain on 29oct15
• Some of this may be the load: dummy load 21oct, antenna 29oct15.
  
• between 21 and 29 oct, some resistors were replaced in the hv vault.
  

Summary

• drive levels for full power

• tx	rf drive dbf	xmitted power
  		rf coupler	KWatts
  tx1	-5.5	16.8	85
  tx2	-6.5	16.2	78
  tx3	-3.5	16.2	78
  tx4	-5.5	16.3	80
  tx5	-2	15.5	66
  tx6	-5	16.0	74

  
  
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• 
  
• 
  
• 
  
• tx5 had lower output.
• monitor ports showed that driver stage had 9 db less gain then 151021 on dummy load.
• see tube stage outputs for 151029
• i swithed from 100K to 1e6 point scope buffers
• channel 1 (broadband output) was set to 5volt scale/div with 1 meg termination
• The 50 ohm termination only allows for 1v/div max
• 
  

  date	ipa output dbm (scope port)	driver output dbm  (scope port)
  151021	-.16	-5.73
  151029	7.74	-6.76
  29 vs 21	7.9 db lower	1db lower

• 
  
• So driver output for 151029 is 9db lower than 151021
  
• ch was at stow.. move it down to za=0 (around 15:04)
  
• test cycling rf on ,off
• 4 sec on , off: low power, medium power
  
• 1 sec on , 2 off  medium power
  
• 4sec on, 4 sec off.. full power
• 1sec on, 2 sec off.. full power
• .5 sec on, .5 sec off.. ran for awhile then gui crashed
• .2 on  .8 off .. gui crashed...
• 1 sec on , 1 sec off
• then tx 1 tripped on reflected power.
• test cycling on right hand polarization phase: (90,0,330,60,30,300)
• 10 db down from ull power
• 5db down from full power
• 3db down from full power
• max power:

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