In a message dated 9/6/01 4:04:19 AM Pacific Daylight Time, n4kg@juno.com
writes:
<<
A 5% lower resonant frequency for the reflector is a good place
to start. It seems to me that one way to do this is to split and
insulate the reflector and then either grid dip the element or
measure the impedance at the center. Once it is tuned, then
it may be joined and mounted to the boom. Yes, there may be
some detuning effects but I would expect them to be small for
a 40M element.
73 / GL, Tom N4KG
On Wed, 5 Sep 2001 "K&L" <kmccourt@tbaytel.net> writes:
>
> Hi All , I am in the process of building a loaded two element 40
> beam. I
> have the driven element finished and its total length is 43` it is
> resonate
> @ 7.150. What would the most practical way to tune the reflector be
> ? Should
> I split & insulate the reflector , mount it on the boom and check
> the
> resonate frequency ? Is 5 % longer a good length ? I am not quite
> sure of
> the best way method to use . Would like to get some input on this .
>
> 73 Kevin
> VE3KKM
>>
I've been able to grid dip aluminum elements without cutting them. If you
have troubles getting a dip reorientate the coil. Plan B is to make a shunt
link of 1 or more turns and connect it to the element with hose clamps.
k7gco.
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