12oct16

# What we did:

• set mesh to 5 MHz ref position
• select 8MHz 8.175 MHz freq
• using phase from 29sep16 rhcp file.
• try to bring all 6 tx up together
• record drive,fwd,reverse powers while doing this
• tx 1,2 tripped reverse power around 35 KW.
• see how reflected power changes as we move the mesh down
• reference position .. recorded values
• 5 feet down .. recorded values
• 10 feet down
• At 10 feet down try to come up to full power all 6 tx.
• got to about 50 KW
• Measure/adjust phases lcp,rcp at 10 feet down -> rhcp_8mhz_161012_low10ft.hfsynth (and lhcp).
• Lunch
• Mesh 10 feet down. use rhcp 10ftlow phases
• see how reflected power changes as we change the frequency:
• 8.175,8.185,8.195,8.165,8.155
• move mesh to 15 feet below 5 MHz reference.
• try seeing how high power would go...
• got to 330 KW total
• tx 6 has trouble.. fwd power meter reads too high..limits how high we can bring it
• Page 1: morning
• Page 2: afternoon
• Page 3: blowup of morning showing tx 4 drifting while drive remains constants.

ToDo

• fit reverse power for each tx:
• rvsPwr_i=c0 + c1* fwdPwr_i   + sum(j=0..5,j!=i, cj*fwdPwr_j)
• plot rvs power as we changed the frequency
• plot rvs power vs mesh height
• flag when changes were made on plots.. (rcp,lcp, freq changes...etc).

# Problems we found:

• Forward power meter tx 6 reads higher than the value from the coupler by up to 30 KW.
• This could be a calibration problem.. But we also saw large harmonics on tx6 ...
• Tx4 output power drifts down by 30% in 20 minutes.
• The reverse power trip points have been set to 7.5 KW.
• this makes it hard to test the 8MHz system because of the large coupling.
• It would be nice if it was possible to raise the trips points back up to 10KW
(where they were before the change).
• With the mesh at the 5MHz reference position, we can't bring the 8MHz system up beyond 35 KW.
• We get reverse power trips. This is coming from dipole coupling, not bad individual vswr's on a dipole
• Lowering the mesh 15 feet (linear on the cable, not vertical) rcp gave us:
• tx1 -  73 KW
• tx2 -  75 KW
• tx3 - 63 KW
• tx4  - 44 KW
• tx5  - 64 KW
• tx6 -  28 KW (meter was reading 86 KW)
• We tried lcp.. this gave lower rvs power than rcp.

processing: x101/161012/procday.pro

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