- This was to the first hf test with the 430MHz tx since
the mar18 campaign.
What we did:
- The mesh was in the 5 MHz position
- we transmitted at 5.125 MHz rcp.
- 430 tx, single beam -> gr. za at za=2.
- gr -> usrp
- ch -> echotek [5.5,9.5]]
- we heard the waveguide arcing up on the platform.
- 11:40 bring up the hf tx.
- 11:50 trouble with tx5 in hv fault (update.. was a
- 12:06 5 tx at 60 kw each..
- 12:15 lots of arcing
- 12:36 turn off 1 tx at a time to see who it was.. then
try 2 at a time.
- not obvious which tx (update. had a load cell cable arcing
(burnt) after the run)
- 12:48 start to bring tx 5 back up.
- 13:00 60KW each of 6 tx.. arcing is less.
- 13:15 70 Kw each tx
- 13:20 cycle mode 1 sec on , 9 sec off.
- 13:35 cycle mode 2 sec on , 8 sec off.
- 13:49 cycle mode off. raise power to 75 KW each tx
- 13:56 cycle mode 2on 8 off
- 13:57 cycle mode off,
- 13:57 cycle mode 5 sec on, 5 sec off
- 14:01 stop cycle mode , raise power to 85 KW each Tx
- 14:12 cycle mode 2 on , 8 off
- 14:24 stop cycle mode
- 14:30 done
HF output power
Plots showing hf tx drive and
output power (.ps) (.pdf)
- page 1:
- Top: hf rf coupler output vs hour of day
- Each color is a different tx.
- the low purple level is when tx5 was offline.
- The rapid changes in power are during cycle modes.
- middle: output power in KW
- bottom: synth drive amplitude (in dbf)
- page 2: hf drive power vs hf output power
- the output power (in KW) vs input drive power (in dbf) is
plotted for each tx.
- values that lie below the trend, occur when an rf off occurs
during a spectrum analyzer power average. cycle mode points
have been removed.
dbf Drive for 85 KW output
- The average drive power for 85KW is -5 dbf.
- tx5 needs 3db more drive
- tx4 needs 4db less drive power.
Generator power vs
The data from the 3 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
Plasma line movies
- Plasma line movies were made using the echotek and the usrp
data. They had 10 sec integrations.
- A higher resolution movie was made with the usrp data. It
blows up the freq and range showing the f-reqion line. The time
resolution is still 10 seconds.
to the movies
- Tx had trouble in the hv fault. The problem was found
to be a broken resistor (it was replaced).
- For the first part of the test we had lots of arcing.
- after the experiment the loadcell cable was found to be
burned. It had been disconnected and left lying on the td yoke
(it will now be removed). This may have caused the arcing.
- we ran cycle modes of 1,9 2,8 and 5,5
at up to 55 KW/tx (510 KW total)
- tx 5 required 3db more drive power than the average value. It
was at close to the drive limit.
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