Just an update on work done this weekend:
I have gone thru disconnecting and testing all the phasing lines in
the 2m-eme array:
1) All eight antenna SWR were individually tested at the driven element.
2) SWR from the TR relay to the Hpol antennas shows SWR = 1.2, Z = 52, j12
I did not disconnect the lines at the 4-way divider as this looks
good (within tolerance of the MFJ analyzer).
3) SWR from the TR relay to the Vpol antennas shows SWR = 1.4, Z = 79, j0
This required individually testing each phasing line, the 4-way
divider, and ten-foot az-el coax jumper.
I found one phasing line with SWR = 3.9, Z = 116, j120. The rest
were SWR = 1.0, Z = 52-54, j0
The 4-way divider with 50-ohm terminations on all ports SWR = 1.1, Z = 59, j0
Terminations vary from 51 to 53 ohms.
4) I will check for open/short ckt on the bad phasing line but
expect to replace it.
The preamp/TR relay enclosure has been completely modified for a
cleaner layout. A 2-foot LMR-400UF jumper was eliminated. LMR-600
directly feeds the relay matrix without jumpers. Wiring and
mechanical mounts were added for a 60w 1296 amplifier to supply the
45 loop-yagi installed at the center of the 2m-eme array. The amp
will temporarily be used for 23cm-eme on the dish but when the 150w
amp is ready for installation at the dish, the 60w amp will be
transferred over here for terrestrial use.
I decided to delay upgrades to the 900-MHz radio until mid-summer
when the 1296 amp will be transferred.
Left to do is some bracing of the 3-inch cross boom and re-alignment
of 2m-XP20 booms; final RF testing at QRO, then the array will be
raised and be QRV (est. 2-3 days).
Remainder of week will be work on the dish getting 1296 QRV with 60w,
and installing a new preamp for 432.
73, Ed - KL7UW, WD2XSH/45
BP40IQ 500 KHz - 10-GHz www.kl7uw.com
EME: 50-1.1kw?, 144-1.4kw, 432-100w, 1296-testing*, 3400-?
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