Wanting to try to phase two end to end Beverages I took several MFJ
Noise Canceller 1026 and 1025 of the shelf and while trying to evaluate
their ability I noticed on both unit that even without any antenna
connected to either input there is a least an S-unit increase in
background noise. One of the units has a built in pre-amp that that was
switched off.
My question: Is this normal? Won't that noise increase mitigate any
improvements I could ever achieve by trying to get a signal enhancement
from two Beverages pointed in the same direction. Both units do a great
job of nulling a AM station on the expansion band right off the front
end of both antennas almost down to the noise. But with the two units
in the null and the phase switched reversed I was expecting an
enhancement in that direction but either Beverage produced higher signal
level when the unit is by-pass by turning it off or with either antenna
hooked directly to the receiver.
Also my two Beverages that I am trying to phase are end to end. Both are
600' long and pointing west. The first one ends where the other begins
with a spacing of 3 feet and with separate ground rods. I have seen
plots, models, and gain figures for broadside or side by side phasing of
Beverages but have not seen anything on end to end attempts. Maybe this
does not work to any advantage. Right now the only thing I have noticed
is the increase noise floor when the unit is turned on and the ability
to null stations from the front, both traits are not needed nor desired.
Any suggestions on this would be appreciated.
Herb Schoenbohm, KV4FZ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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