Introduction:

Testing sequence:

• Data was recorded from the ch receiver using the interim correlator
• the telescope was parked at:
• gr az=285, fch az=105,  ch za=8.8, ch dome=10.
• ch was within 15 deg of td 4..
  
• to minimize arcing in receiver.. it would have been better to put is at 270, 90.
  
• We phased the array using the file:  rhcp_2.hfsynth (rhcp).
• 08:00  -started to bring up all tx (except tx4. it had an air valve problem)
• 08:30  -tx up to around 15 dbm on coupler
• 08:40  tx 4 brought up.
  
• 09:30  raised the drive a little
• 09:51  raised the bias on tx 4 a little (and the output power went up)
• 10:36   power recorded from ch jumps by about 3db..
  
• All tx (except tx4) was brought up together
• tx 4 had a problem with an air valve.. it was fixed and then brought online. (8:40 am)
• 10:40   increment drive to get around 80-85 kw.
• 11:10   stopped

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.

• Page 1: entire run: 7:50 to 11:10
• Top antenna drive (db full scale).
• tx 4 came online at 8.6 (8:36)
• The red line shows the ch power (db scale)
• There was a jump in the ch power at 10.6 (10:36).
  
• bottom: phase for each tx.
• This was right hand circular. we did not change the phase during the run
• Page 2: bloup of 9.5 to 11.2 hours
  

carriage house spectra and dynamic spectra

over plotting the spectra:

   25 MHz 1sec dump spectra were taken with the interim correlator during the entire run.
The long range recievers were selected.

ch spectra 10.0 to 10.5 hours (.pdf)

• the harmonics of 5.125 MHz are flagged.
• pol A and polB where averaged..
• This was before the total power jump at 10.59 hours.
  

• this is after to total power jump at 10.59.
• the jump was across the band (the noise floor increased by 3db).
• other strong birdies have also appeared

dynamic spectra 10.6 to 11. 1 hours

    The first image shows the dynamic spectra scaled to 5 sigma (.gif)

• the horizontal lines at 10.65 and 11.0 correspond to the total power jumps seen in the hfsynlog plots.

• the 5.125 mhz harmonics are visible as vertical lines at: 425.375,430.5,435.625, and 440.75 MHz
• a strong birdie at 429.5 is also visible
• around 11.0 there were strong bursts at 430.0, 431.0,431.5, and 432 MHz. these look like periodic bursts.
  

.

rf drive and output power. tx output stability.

    The rf drive  and total output power (KW) where plotted for the 3 hour run (ps) (.pdf)\

• Each transmitter is plotted in a separate frame
• The black line is the kilo Watt output power (as measured from the rf coupler).
• the red line is the rf drive  (linear scale).
• I scaled it so that the maximum output value we used was 80.
  
• Page 1:
  
• top tx 1
• middle tx2
• at 30 minutes the output was 87 Kw. it then drifted down to 65 Kw (without changing the drive).
• bottom: tx3
• Page 2:
• top: tx4
• tx 4 came online at 50 minutes.
• middle: tx5.
• at 30 minutes tx5 went to 68 Kw. it then drifted down to 55 Kw in 20 minutes.
• bottom: tx6
• at 30 minutes tx6 went to 80 Kw. It drifted down to 65 Kw in about 30 minutes.
  

Summary

• We melted the end of the load cell cable on td 4.
• They unplugged the cable from the huffman box side. It was left connected to the load cell
• It should have been disconnected at the load cell.
• drive when at max power (max for the day).
  

• tx	rf drive		xmitted power
  	drive  dbf	phase deg	rf coupler	KWatts
  tx1	-5.7	106.0	16.8	85
  tx2	-8.0	0	16.2	78
  tx3	-3.9	345.5	16.2	78
  tx4	-5.0	57	16.3	80
  tx5	-2.5	72.5	15.5	66
  tx6	-6.6	297	16.0	74

  
  
• 
  
• We saw burst of noise.. when starting up, and again around 11.0 (maybe this was the cable end arcing).
• there was a 3db jump in level in the ch receivers around 10.6.
• tx 2,5, and 6   drifted down in power by 15-25% in about 20 minutes after being brought to full power.
  

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