[TowerTalk] Increasing power capability of 6-meter yagi

[Joe Subich, W4TV]

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?
>