Background:

• Problems during previous test  26jan17:
• tx 5 arcing from tx output 5 MHz filter. This was worked on since 26jan17.
  
• tx 2 and 4 were tripping on reverse power. at 5 and 8 Mhz.
• tx4 had driver a/c power trip running 8MHz.
  

What we did:

• 10:20  start
  
• mesh at 5 MHz position. tx at 5.125 Mhz
  
• 11:06  6 tx brought up to 40KW (each tx). for 10 minutes
• 11:18  start to raise power to 80KW (each tx)
  
• tx 4 trips with driver A/C error (need to check this error).
• tx4 remains off for about 1 hour
  
• 11:24 tx 2 output power goes from 80KW down to 50KW without changing the drive level.
• the broad band output was showing 50W with syn drive level of -9.1dbf. The other tx were around 150-400.
• 12:00  cycled hv on tx 2. syn drive -9.3dbf, broad band 90W and output power 80KW. So it was back to normal.
  
• Note sure what caused the drop.
• the input drive level was normal (we checked the input to the broadband).
  
• 12:18  tried bringing tx 4 back up. Came up for 15 minutes then tripped. Saw arcing in the power supply vault.
• 12:36 ran 5 tx (1,2,3,4,6) at 80 KW
  
• 13:24  bringing up 430 Tx, start datataking recording. echotek [5.5,5.5] gr,ch -> testhf_ file. ch -> usrp
  
• az=285,zach=8.83  zagr=11 .. so ch,gr were pointing out of the heating beam (+/- 7deg).
• 13:55 start auto toggle 3 sec on, 3 sec off.  80 KW on (1,2,3,5,6)
• 14:06 stopped cycling. readjusted output power to around 75 KW each tx.
• had drifted up to 90KW.
• restarted auto toggle
  
• 14:24 stopped auto toggle, rf off. Move mesh to 8Mhz position (15 feet low).
• switched grplasmaline to 7.0  Mhz cfr  for echotek.
  
• 14:44 start bringing up 8 mhz on tx [1,2,3,5,6] at  8.175 Mhz.
• sit at 50KW for about 10 minutes
• 15:00 80 KW on  5 tx (400KW total output power). tx 4 is off.
  
• 15:36 tx 6 trips on driver a/c 3 times. turned off 16:06 to 16:24
• 16:00 tx 4  brought back up (after cleaning things in the HV vault).
• 16:24 all 6 tx now up at 80 KW each.. 480 KW total output power.
• 16:33 turn off transmitters, done with test.
  

Plots of output and drive power:

The plots show the data we took while the hf was on (.ps) (.pdf)

• Each page has 3 frames:
• each color is a different transmitter (1 through 6).
  
• top  frame: rf power (in dbm) measured at the output of the rf coupler.
• middle frame: the same output power, but displayed in KWatts
• bottom frame:
• The synthesizer drive amplitude used
• The dashed green line shows when the rf was on
• the red line at the bottom is the total power from the carriage house 430 receiver (polA 425-435 MHz). When we have arcing, there are jumps in this power (rfi can also make jumps).
• Page 1: 11:00 to 14:30 5MHz testing
• tx4 (blue) trips with driver a/c. stays off for most of the 5 Mhz test.
  
• tx2 (red) drops from 80KW to 50 KW around 11.5 hrs. after resetting twice, it came back to 80KW with the same drive level.
• the jump in the ch  tp monitor at 13.4 was when the 430 Tx was turned on.. The 430 tx setup changed the levels.
  
• around 14:00 we started the auto toggling..
  
• Page 2: 14:42 to 16:30 8MHz testing
• tx 4 (dark blue) remains down until 16:00
• tx 6 (light blue) starts tripping around 15.6
• all back up at 16.4

plasma line movies while hf on

• 13:28 to 14:50  transmitting 5MHz
• 13:55 to 14:24  auto toggle
  
• 14:50 to 16:29  transmittting 8 MHz

Summary:

• we did not see any arcing on the ch total power monitor (interim cor).
  
• Looking at the clp data, we can see arcing. especially with the 8 mhz.
  
• tx 4 and tx 6 had trouble with arcing in the HV fault
• people were cutting out slabs of cement in the tx room floor during this test.
• We need to check that the cement dust was not getting into the HV vault, causing these problems.
• tx 2 (running at 5 Mhz) dropped it's power from 80KW to 50KW without changing the drive levels.
  
• the broad band dropped from 90 to 50 Watts.
• We checked the input drive level to the broadband, and it did not change.
  
• 5 Mhz. we ran 80*5 =400 KW for 1 hour
• 8 Mhz  we ran 80*6 = 480 KW for 10 minutes.
• tx 6 broad band was running at 400 Watts with 80KW output power.
  
• Alfredo adjusted the biases, it then had 300+ Watts output for 80KW.
• For a long run, we may have heating problems with the broad bands running at this level.
• The recommended broadband  level for 100KW output is 70 to 140 Watts.

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