What do you mean by linear loading?
How long are your radials?
73, Petronel YO8SEP
On 21 Dec 2016 22:43, "Patrick Armstrong" <ft920ir@gmail.com> wrote:
> I have noticed several times that people talk about being able to put
> up a full .250 wavelength vertical and I have wondered why almost never do
> they think about making it .270 wavelength instead of .250 wavelength. The
> little extra length gives a feed point impedance of 52 ohms with some
> inductive reactance which can be canceled with a series capactor. This
> gives a more efficient feed than a .250 wavelength and using an inductor to
> get a match. I designed my 75/80m vertical this way and with 65 radials (
> odd number 'cause that's all the wire I had) it has allowed me to work 280
> entities with100 watts, all SSB. (Blasphemy I know, I have an ear
> condition which made 13 wpm almost impossible for me).
>
> I also use this antenna on 160m by using linear loading and an inductor
> for matching. Linear loading seems to be overlooked in a lot of discussions
> of antennas on this list and I wonder why. Am I missing a downside to these
> matching systems? If so I would like to hear about it.
>
> Pat Armstrong KF5YZ Heart of Texas
>
> On Tue, Dec 20, 2016 at 12:00 PM, W0MU Mike Fatchett <w0mu@w0mu.com>
> wrote:
>
>> https://www.dxengineering.com/search/product-line/dx-enginee
>> ring-160-meter-thunderbolt-vertical-antennas?autoview=SKU&
>> keyword=160%20vertical&sortby=BestKeywordMatch&sortorder=Ascending
>>
>>
>> On 12/20/2016 10:24 AM, Petronel Postolache wrote:
>>
>>> I can't find the Vertical from DX Engineering. If you can send me a link
>>> it will be great.
>>> One solution might be top hat vertical, similar with
>>> http://dl2kq.de/ant/3-1.htm . Not sure how much power is lost in the
>>> matching unit L1, C1.
>>>
>>> I would love a Waller Flag too. Imposible to buy one from here (too
>>> expensive) but I might wanna try build one. Preamp will be the biggest
>>> problem.
>>>
>>> Petronel
>>> YO8SEP / YP8W
>>>
>>> On Mon, Dec 19, 2016 at 9:30 PM, W0MU Mike Fatchett <w0mu@w0mu.com
>>> <mailto:w0mu@w0mu.com>> wrote:
>>>
>>> Check out DX Engineering. They sell a vertical that uses 3 top
>>> hat wires. Sloping back down is ok. For 80/160 you need to stop
>>> the 80m energy with a coil/trap My 80 uses a very fast taper and
>>> the top is only 3/8 inch or less so It cannot support a coil or t
>>> wires. I probably should have planned that out better. I was
>>> also going to try to phase two 80 elements over time but that will
>>> not happen any time soon.
>>>
>>> With all the metal in the yard the AY loop may not work very
>>> well. Waller Flag on the roof maybe. I would love one.
>>>
>>> W0MU
>>>
>>>
>>> On 12/19/2016 12:24 PM, Petronel Postolache wrote:
>>>
>>>> I can try to put a 21-22m (68-70 foot) telescopic aluminium pole,
>>>> made from pipes 2" to 1" diameter.
>>>> It will be a bit too long for 1/4 on 80m. I can put a T top hat
>>>> or run an InvL, but probably need to slope it from 70 foot to
>>>> about 40 foot. What will be better ? and will I be able to
>>>> match/use the antenna on 80m also ?
>>>>
>>>> About K9AY, I understood that the loop is influenced by close
>>>> metal objects, and the property is full of wire fences, vineyard
>>>> rows and other "metal" structures. That's why i was thinking
>>>> about using some flag/loop at 10 feet or more above ground.
>>>>
>>>> 73, Petronel
>>>> YO8SEP
>>>>
>>>> 160 and 80 will be difficult. Can you get another vertical up
>>>> about 60 feet? You can top load that with a trap for 80 and have
>>>> "t" wires at the top that also act as guy wires. You can also
>>>> bottom load for 160 and maybe that will be good enough for you.
>>>> Radials whatever you can do will help.An Inverted L with about
>>>> 50ft of vertical will work ok....If you can keep the horizontal
>>>> end up in the air around the same height or more. It doesn't
>>>> sound like you have any tall trees to work with.For receiving I
>>>> have been very impressed with a K9AP loop. 25 ft up and about 15
>>>> feet out at the corners. It does not take up much space and you
>>>> can reverse the direction easily with a relay. A flag or pennant
>>>> will work too. You can never have enough rcv or xmit antenna! HI!
>>>> Welcome to the club!
>>>>
>>>> W0MU
>>>>
>>>>
>>>
>>>
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