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2M-22C antenna polarization question



Hi, All

>From the last week I am using a 2 meters KLM antenna  model 2M-22C
and it works very well but just for technical curiosity I have a question
concerning the suggested RHCP and LHCP connections.

The instructions manual (Rev: May 5, 1994 ) page 3 paragraph 5 states:

"For the unenergized RHC (right-hand circularity), connect the center lead
to the RIGHT feedpoint stud of the horizontal dipole view from rear of boom"

I did it to get RHCP with relay not DC supplied but receiving satellite
signals I realize that the above connection is wrong because as compared
with different antennas receiving the same signals the suggested connection
make the antenna LHCP and not RHCP

The only way for me to theoretically investigate on the electrical field
rotation would be now to remove the PCB of the polarity switcher from the
vertical dipole and inspect if the 1/4 wavelenght 75 ohm coax cable is
connected to the upper end or to the lower end of the vertical folded dipole
as depicted in page 6 of the manual.

Unfortunately before to put the antenna on the tower in a hurry I forgot to
make a schematic diagram and a drawing of the PCB with relay and actually
I dont like to lower again the tower.

If someone has in hand the PCB with relay disconnected from the folded
dipole he can measure with easy if the coax cable going to the common of
relay after passing through the NC contact (relay not excited ) is connected
to the upper or to the lover end of the vertical dipole as depicted in fig-6
of the manual after that I can fix if using the suggested connection the
antenna radiates RHCP or LHCP

Tanks for any help.

73" de

i8CVS Domenico
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