If you've got a C-3 (any sort) stacked with a direct dipole feed antenna
(tribander or monobander), I'd love to talk to you about it.
I've been modeling a stack for the 10 meter contest of a C-3E and a 3
element direct dipole feed 10 meter monobander. My models show that the 10
meter portion of the C-3E has about a -145 to -160 degree phase shift. This
means that when you stack it with a monobander like mine, the antennas are
practically out of phase (and so you get very poor results at low angles of
radiation).
I need to know if this phase shift is real, or is a result of modeling error
on my part. I'm not going to have much time to get this stack up before the
contest, and I'd like to know exactly what I am going to install and how it
is going to work before I climb (if possible - obviously, it is never
possible to be completely prepared). Obviously, I can cut a delay line to
adjust for the phase delay, but I need to be confident that:
a) the delay really exists - I've heard rumors that others have such a stack
and it works without any delay line, and
b) the right length to cut the delay line
I just won't have time to experiment once the antennas are up - either I get
it right or it waits for next year.
Thanks for any thoughts,
***dan, N6BZA
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