Table of what we did  (top)

Transmitted power: (top)

Hf transmitter

The transmitted power was measured for each hf transmitter. The setup was:

• rf output coupler from each tx  goes to rf multiplexer (hanging in front of blue cabinet in hf ctrl room)
• output of multiplexer to fieldfox spectrum analyzer.
• fieldfox setup:
• 0.. 20 MHz, rbw 300 khz,
• minhold, maxhold, avg 6 seconds
• the ffcom program controls the fieldfox and the hfswitch
• 6 secs each tx, then move to next..
• data stored in /share/phildat/hf/yymmdd

• black trace: average power for the 6 seconds
  
• red trace: peak hold value for the 6 seconds
• green trace: min hold value fo the 6 seconds.

Experiments by day (top)

24jun20 14:00 to 18:00 ( top)

• pattern: 4min on, 1 min off.
  
• siggen routines:
• on4off1.cmd
• used 10Khz clock. Delay from tick to rf output to tx : 100usecs.
  
• times:
• 14:00 start 4min on, 1 min off
• 14:45 tx4 tripped.. brought back up
• 14:53 tx4 tripped offline
• 14:57 tx4 back online
  
• 16:30 turn hf tx off for 15 minutes (but request of user)
• used rf toggle switch. 
  
• this left a small leakage into the tx (hf tx output power probably a few watts)
• a few seconds later included the siggen rf off. this cut off all drive to the.
• 16:52   tx output dropped  500KW -> 400Kw
• one of the generators tripped off
• we had 2 2MWatt generators
• running on one generator
• 17:15 adjust tx drive to get back to 500KW (using 1 generator).....
• 17:45   tx 4 tripped when going 1 min off to 4 min on
• 17:48  tx 4 back up

25jun20 13:00 to 17:00 ( top)

• pattern: 5 min on, 5 min off.
  
• siggen routines:
• on5off5.cmd
• used 1KHz siggen clock. delay tick to rf output to tx: 1ms.
  
• times:
• 13:00 start 5min on, 5 min off.
• 14:30  tx 5 drifting down a few .1's of a db. nudged it back up by increasing the drive.
• 16:55  end last 5min tx on.
• 17:00  exp done.

26jun20 13:00 to 17:00 (top)

• pattern: 5 min on, 5 min off
• siggen routines:
• on5off5.cmd
• used 1KHz siggen clock. delay tick to rf output to tx: 1ms.
• times:
• 13:00 start 5min on, 5 min off.
• 15:50 tx1  tripped. PA screen.. brought back up.
• 16:55  end last 5min tx on.
• 17:00  exp done.

How the hf transmitters were controlled

• There are 6 hf dipole antennas. 3 radial and 3 tangential.
• The ao SynGui was uses to generate the 6 phases needed to generate rcp polarization.
• file rhcp_5MHz_80kw_200611.hfsynth was used.
• It also supplied programmable attenuation to the 5.1 MHz drive signal.
• these were sent to the ao phaseshifter.
  
• 2 keysight signal generators were used to generate the gated 5.1 MHz sine wave used to drive the hf transmitters.
• The signal control path was:
• siggen c program running on linux.
• controlled the 2 hp siggens : siggen 1 and siggen2.
• /share/megs/phil/svn/aosoft/src/siggen/siggen.c
  
• siggen2 : gate siggen 1
  
• was loaded with an arbitrary waveform that would turn siggen 1 sine wave on and off (eg 4min on, 1 min off).
• It was triggered to start on a hardware 1 second tick (1 siggen clock cycle after the tick .. 100usec or 1000 usec depending on clock used).
• the siggen program would load both siggens and then wait until 1 second before the minute and then tell siggen2 to start on the next tick.
• The output of siggen2 was sent to the trigger/gate input of siggen1.
• siggen1: generate 5.1 MHz sine wave
• It was loaded with a 5.1 MHz sine wave at 4.3dbm
• It was placed in gated mode (driven by siggen 2)
• After loading, it was gated in the off state until siggen2 gave a high on the gate.
• output of siggen 1 -> 5MHz filter -> power splitter-> radial and tangential inputs of ao phase shifter
• ao phaseshifter applied the 6 phases need to get rcp. Programmable attenuation was also applied.
• output of ao phaseshifter -> broadband inputs of the 6 hf tx.
  

siggen programing notes

• 
  
• siggen 1: output the 5.1 MHz sine wave (at 4.3 dbm since we also used the 5MHz filter).
• the output of siggen 1 was gated by the output of siggen 2.
• siggen 2: ran an arbitrary waveform that had a hi  output for a specific duration then a low output for a 2nd duration.
• we used this to generate the 4 min on  1 min off ,and the 5min on  5 min off patterns.
• The output of siggen 2 drove the trigger/gate input of siggen 1
• siggen 2 was triggered on the hardware 1 second tick.
• The siggen program (/share/megs/phil/svn/aosoft/src/siggen/siggen.c) was used to configure and drive the siggens.
• the command files used were:
• 2020_06/on4off1.cmd   and 2020_06/on5off5.cmd 
  
• Each of these programs used  the start on next minute command.
• These were selected using code 3 (command file from withing siggen)
• You would
•  enter 3,
  
• enter the command file name (eg 2020_06/on5off5.cmd)
• wait  until about 50 seconds before the the next minute and the hit return
• The routine would load the siggens and then wait until 1 second before the minute, then tell siggen2 to start on the next hardware tick.
  
• The siggen program was run via:
• cd /share/meg/phil/svn/aosoft/src/siggen
• siggen --hf  --siggenuse=12
• gotcha's on running the  program
• be sure and turn off the hf drive  switch before starting the siggen program
• it resets the siggens and the output something like 1MHz
• after loading the siggen program and sending a command file, you can re enable the rf toggle switch.

fof2 for the 3 days (top)

• 24,25jun20 (.png)
• Red trace is 24jun20
• blue trace is 25jun20
• 25,26jun20 (.pdf)
• Red trace is 25jun20
• blue trace is 26jun20
  

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