On Feb 28, 2025, at 5:59?PM, Larry Acklin via groups.io <acklin@...> wrote:

?

I used to have issues with my FT901 like that, CW would stick in transmit- RF in the shack. A ferrite slug with 6 wraps of the shielded?CW key lead after it left the external keyer fixed it.?

My EFHW starts at 30 ft and slopes to 10, counterpoise drops to 6 ft and runs along roughly the same route. 40, 20, 15, 10 all acceptable SWR. 49:1 balun feeds coax to the radio.?

Larry

KB3CUF?

On Fri, Feb 28, 2025 at 2:57?PM jerry-KF6VB via <jerry=[email protected]> wrote:

Hello all,

? ? I was trying out my station with a second antenna - an 65-foot End
Fed Half Wave.? I had built it to the kilowatt level, with a big toroid
core on the matching transformer.? Instead of a counterpoise, I used an
8-foot ground rod - the kind they sell to ground your house.
Probably needs a counterpoise also...

? ?The far end of the antenna is supported by a monster oak tree on my
property.? Got it up there with a slingshot.

? ? I hooked up a spare MFJ998RT autotuner to the EFHW and thence to my
station through
a 40-foot length of Davis Buryflex RG/8.

? ? It worked fine on the base T41 - decent SWR on 40, 20 & 15M.? And it
actually worked
on 80 - although the autotuner was clearly struggling.

? ?HOWEVER, when I turned on my KW amp, I pushed the PTT, and the power
immediately rose to 950W or so out...without me talking.? And somebody
on the frequency said "what's that noise?".

? ?I figure that RF is getting back into the T41.

? ?Probably need to stick a counterpoise on the EFHW, and maybe a common
mode choke.

? ?My main antenna does not give me any such problems;? it's a trap
vertical up the hill,
and it has an excellent ground - an Ufer ground, consisting of 80 feet
of thick copper wire embedded in a 10 by 70' concrete slab.

? ?I'm trying the EFHW to see if it's any quieter than my vertical.? So
far, it's about the same.

? ? ? ? ? ? ? ? ? ? ? ? - Jerry, KF6VB