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CP phasing harness: Coax Substitution?



I'm building a phasing harness for a 435 MHz cross-yagi antenna.  The plans 
call out RG-11 for the odd quarter-wave sections that connect the antennas 
to "N-type" tees back at the coxial relay.

RG-11 has proven a little tough to find.  Would RG-59 of the same impedance, 
same velocity factor, and same capacitance per foot as the RG-11, be an 
acceptable substitute?

I have the same issue with the RG-133 that connects the back sides of the 
tees together.  I've found some RG-62 that seems to be identical except for 
the velocity factor and the capacitance per foot.  The length for this part 
of the phasing section can easily be scaled given the velocity factor of the 
coax, but the capacitance between RG-133 and RG-62 differs by 2.5 pF per 
foot.

Are there some other characteristics that should be taken into account when 
making substitutions like these?  I realize that there may be differences in 
loss at that frequency, but the runs will be very short.  Your thoughts, 
please.

Thanks,
Steve -- K6UX
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