On 1/2/2012 2:08 PM, K8RI wrote:
> On 1/2/2012 7:27 AM, Mike wrote:
>> On 1/1/2012 5:34 PM, K8RI wrote:
>>> On 1/1/2012 1:56 PM, Mike wrote:
>>>> I need to replace the attachment for my 160/80 meter 1/4 wave sloper (fed
>>>> at the same
>>>> point, attached to one leg of the tower). I'm currently using an
>>>> Alpha-Delta sloper
>>>> connector, but it's in bad shape after 19 years. Suggestions?
>>> This is what I did:
>>> http://www.rogerhalstead.com/ham_files/tower46.htm
>>> http://www.rogerhalstead.com/ham_files/tower47.htm An example of how it
>>> mounts to the tower leg.
> To to along with the photos, I took a piece of 3/4 X 1/8" Aluminum
> about 8 or 10 inches long. Securely clamped the Aluminum in the drill
> press, drilled the hole for the SO239 using progressively larger drills
> so they didn' take too big a bite at one time. After the SO239 became a
> slip fit, I clamped the piece in a vise to make the 90 degree bend. I
> thoroughly sealed the fitting using flooded heat shrink and liquid
> electrical tape. Just in case there is also a drip loop that
> immediately goes higher than the connection when installed. The two SS
> hose clamps are all I use to hold the fitting. The insulator is held to
> the tower by a short piece of 3/16 nylon braided rope. This removes the
> strain from the fitting.
>
> I had to move the resonance from the bottom of 160 to around 1925 or 50.
> With the antenna resonant lower, the tuner would arc with much more than
> a 100 or 200 watts when I'd try to operate near the top end of the
> band. This would be a great place to mount a remote tuner and feed the
> half sloper like an end fed wire.
>
> 73
>
> Roger (K8RI)
Thanks for the extra details. My wires are 1/4 wave, and both 160 and 80 are
fed from
the same point. Seems like mounting it downside up and having the heatshrink
cover
enough of the coax to allow the end of the heatshring to be on the down hill
end of
an upside down "U" might provide better drainage. Course if the choke is in
line,
that's not a great idea either.
The wires come down not quite 180 degrees apart. I think maybe constructing it
of a
piece of AL angle so it stands away from the tower a bit so the wires clear the
tower
might work.
I don't have a tuner, other than in the rig, and am trying to avoid acquiring
one ......
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