- This was to test the hf prior to the 15mar18 hf run.
- 180307 test showed tx 4 had large reflected power.
- the next day up to 2 gallons of water was removed from
the heliax line by the splice under the bowl.
- This was probably leakage from when the splice was under
water after hurricane maria. (lago arecibo :).
What we did:
- The mesh was in the 5 MHz position (i assume..)
- we transmitted at 5.125 MHz rcp.
- Only 2 generators were available to provide power to the hf.
the 430 tx was on commercial power.
- 430 tx, single beam -> gr. za started at 1.06 then moved to
- gr -> usrp
- ch -> echotek [-5.5,5.5]
- we heard the waveguide arcing up on the platform.
- 10:10 bring up 430tx (approx)
- 11:00 rf off 430 tx.. we could hear arcing upstairs.
- 10:54 hf rf on.
- hftx 1-5 come up ok
- hftx 6 won't come up. filament timer is not timing out.. run
with 5 tx till 14:05 when tx 6 comes up.
- 11:13 rf off
- 11:14 rf on for 30 secs then back off.
- 11:33 rf on
- 11:50 rf off
- 11:54 rf on
- 12:06 bring power up to 60*5 kw
- 13:00 start recording 1 sec spectra with interim cor.
- 13:06 raise power 65*5
- 14:05 start bringing up tx 6.
- 14:06 looks like tx1-5 rf switched off while 6 comes up
- 14:12 all tx back up
- 14:18 raise power.. shooting for 70kw*6
- 14:23 gen 3 trips with coolant over temp..
generators shut down.
HF output power
Plots showing hf tx drive and
output power (.ps) (.pdf)
- Top: hf rf coupler output vs hour of day
- Each color is a different tx.
- the low blue level is when tx4 was disabled.
- middle: output power in KW
- bottom: synth drive amplitude (in dbf)
- The red line with noise it the total power from the
gregorian receiver measured with the interim correlator
- This was started around 13:00
Generator power vs
The data from the 2 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
- generator 3 had a low pressure, then pre high temp warning..
- Tx 4 no longer had reflector power.. it worked ok after
removing the water from the heliax.
- previously S11 measurements were done with the water in the
- The values measured did not show a problem. it would be
interesting to re examine the data (if it was recorded).
- Tx 6 had trouble with the filament timer relay. It was fixed
- We had lots of arcing.
- we ran 350 KW using 5 transmitters.
- The low pressure warning on gen 3 occurred during this
- With 6*70KW gen 3 tripped with high coolant temp
- The generator mechanic cleaned the airflow for the motor
radiator after this run.
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