[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Circ. Polarized antenna question/idea

Hi folks,

    Was looking at some of the various circular polarized antennas on the 
market today with a friend who is also looking at getting on the digital 
birds and we were discussing antennas and he explained to me about circular 
polarization.(HINT: HE IS A ENGINEERING PROFESSOR AT W.V.U.) After our 
discussion of how to make a antenna circular polarized I began to thinking 
about looking into trying to build a circular polarized 436 quagi based off 
of the quagi designs shown on K5OE's web pages and even thought of trying to 
build a 145 version also.

    So is there anyone out there that has tried this with or without success?

    As I understand it, the 2 antennas would be of oppsite polarity, verticle 
and horizontal, and they would be spaced 1/4wavelength/90degrees apart on the 
boom as far as elements.  The feeds would be independent to each polarity, 
however a 1/4 wave phassing line would be used to joint the 2 antennas into 
one feed and by switching which ant. the phasing line is in-line with would 
control the RH/LH polarization factor.

    So since I have phased dual beams in the past for weak signal work I used 
1/4 & 3/4 sections of 75ohm coax to make a phasing harness and was thinking 
that by using the same 1/4wave section design with equal length 50 coax feeds 
from the quagis to a feedpoint control would work in this plan also?

    Any suggestions as to which phase to let lead and which one to let 
follow? Verticle before Horizontal or Horizontal before Verticle?

    Any advise or suggestions would be really helpful, except ones that say 
just go use the credit card at AES as my WIFE has the credit cards on hold 
till after Christmas shopping is over...

73's Jacob Tennant,KB8QIR
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org