On 2022-07-31 9:01 AM, Pete Smith N4ZR wrote:
It looks to me that this limitation might relate to the feedline
connection, which is a bulkhead SO-239 (mounted with a big nut)
bracketed to the center of the driven element.
I would bet that the limitation is due to the breakdown of the
dielectric in the gamma match (capacitor). CushCraft used a
rod from the center conductor of the UHF connector through a
dielectric tube inside an aluminum tube that formed the outside
of the gamma match.
If 1KW is a real limitation, I doubt that you can do anything
to improve it except redesign the antenna for a split driven
element and 50 Ohm feed. That 7' boom would make a nice 4 element
OWA.
73,
... Joe, W4TV
On 2022-07-31 9:01 AM, Pete Smith N4ZR wrote:
I have just bought a small Cushcraft 3-element 6-meter yagi. Only small
fly in the ointment is that it is *only* rated at 1 KW. It looks to me
that this limitation might relate to the feedline connection, which is a
bulkhead SO-239 (mounted with a big nut) bracketed to the center of the
driven element.
My question is, do I need another connector here, or maybe insulation
between the bracket and the element? If so, what material makes sense?
Any other advice?
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