From:
Fred Hopengarten K1VR 781/259-0088
Six Willarch Road
Lincoln, MA 01773-5105
permanent e-mail address: fhopengarten@mba1972.hbs.edu
K1VR: My TH6/TH7 stack is at 97'/61'/31', with guy wire sets at
90'/60'/30'. When I had a two stack (97/61) performance was GREAT on 20
and OK to good on 15. It sucked on 10. The single TH7 at 36' beat it
every time into EU (high angle, high rate). The high TH6 is still the
best into the far western Pacific and Japan (low rate, low angle).
On Mon, 28 Sep 1998 08:53:17 -0400 Pete Smith <n4zr@contesting.com>
writes:
>See my article in July-August 96 NCJ for a first attempt at modeling a
>C-3
>stack. My results tended to indicate that a spacing of about 28 feet
>gave
>a decent compromise between gain on 20 and degradation of F/B ratio on
>15.
>The 10-meter case is pretty far outside the normal stacking range
>anyway
>(almost a full wave).
>
>I also recently looked at a 3-high stack of C-3s with the antennas
>only
>about 20 feet apart, thinking that I might get better performance on
>15 and
>10, then "cut out" the middle one on 20. Trouble is that you can
>disconnect the feedline but all those resonant or near-resonant
>elements
>are still there, so the 20-meter performance looks terrible.
>
>My current plan, for whatever it's worth, is to install a C-4XL at 97
>feet
>-- building it now -- and stack a C-3 at 69. Since the 10-20 meter
>sections are identical, that should give me good 10-40 meter
>performance.
>I know Tom'll say I need a third C-3 down at 35 feet or so, but one
>thing
>at a time!
>
>
>73, Pete Smith N4ZR
>In wild, wonderful, only middlin' rare WEST Virginia
>
>
>
>--
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>
>
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