Topband: 5/16 vs 1/4 wave length inverted L
Guy Olinger K2AV
olinger at bellsouth.net
Thu Aug 5 14:10:08 PDT 2010
Aside from miscellaneous capacitance, which won't amount to much on
160, just changing the feed a little, I don't see any real effect.
You should connect the metal house to the radials and to your ground.
On Thu, Aug 5, 2010 at 1:58 PM, tzikas tzik <tzitzikas77 at gmail.com> wrote:
> hi again. I have a more question. As you can see at this draw
> the feedpoint of my antenna is founded in the transmitter's metal house!!!
> I have put the feedpoint there because i wouldn't like somebody to touch the
> feedpoint and to have an accident.
> Do you think that this is a problem for my antenna's performance?
> The antenna (from 2mm diameter insulated wire) begins from the transmitter
> and then passes
> through the metal house. The antenna's wire which is in the metal house is
> about 1.5 meters.
> Also the redials begins in the metal house.
> On Tue, Jul 27, 2010 at 12:11 AM, Guy Olinger K2AV <olinger at bellsouth.net>
>> There is very little difference in the pattern of a 5/16 inverted L
>> and 1/4 inverted L that has the bend to horizontal at the same height,
>> assuming a bend even roughly half way. The lower the bend the higher
>> the maximum lobe takeoff, but it's a mild change. 29 degrees vs. 49
>> degrees is not correct, all other issues held constant.
>> 73, Guy.
>> On Sun, Jul 25, 2010 at 11:49 AM, tzikas tzik <tzitzikas77 at gmail.com>
>> > Hi. I have a transmitter for 160m band about 200-300w r.f output power.
>> > Now
>> > i am using an (5/16)X(wave length) inverted L. I am looking for an
>> > antenna
>> > which will provide strong local signal. I have read that the 5/16
>> > inverted L
>> > has about 49o elevation angle and the 1/4 inverted L has about 26o
>> > elevation
>> > angle. So, i think that 1/4 inverted L, provide more strong local
>> > signal.
>> > what do you think about this?
>> > Now with 5/16 inverted L it very easy to match it with the 50ohm
>> > transmitter
>> > by using only a series variable capacitor. I am afraid that with 1/4
>> > inverted L it will be more difficult to match it with the transmitter.
>> > What
>> > i need (coils and capacitors) to match it? thank you very much
>> > _______________________________________________
>> > UR RST IS ... ... ..9 QSB QSB - hw? BK
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