Let's do some quick math.... 234/1.82=128.57 gives us the length in feet of a
quarter wave at 1.820 mHz. Multiply that by a velocity factor ( say 85% for
LMR-400) and you get a length of 109.29 feet. The math will tell you that for
every percentage point of velocity factor, it equates to 1.28 feet or 15 and
7/16 inches. Every degree of phase will then be 1/90 of the quarter wave length
times the velocity factor. In this case, using 1.820 Mhz and a velocity factor
of 85 then the equation is ((234/1.82)*0.85)/90=1.214 feet or 14 and 9/16". If
you are reasonably careful in your measurements, your phase length will be
fine. It comes down to accuracy of published velocity factor but I don't think
it will present much of a problem. Move up to gHz frequencies and it's another
story.
73,
Jim W5QM
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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