I haven't followed this closely. If you're looking for log periodic yagi
that covers amateur frequencies I just happened to pick up a QST, June
2013, pg. 56 "Short Takes" column by Steve Ford, WB8IMY. There, he reviewed
a hand held VHF/UHF Log Periodic Yagi from Elk Antennas, model 2M/440L5.
It has 5 elements and costs $125. They're in Walnut Creek, CA. Ph: (925)
330-0049. www.elkantennas.com
If that company that makes hand held amateur yagis out of aluminum arrows
is still around that may be another option. Arrow Antennas?
I don't know if it is a universal feature of log antennas but Scala
recommended using one of their commercial log periodic antennas to help
solve a multi-path problem (actually, I needed to attenuate a silmulcast
signal from another site. Their antenna's very clean pattern with virtually
no side lobes and high F/B helped do the trick. I pointed the antenna to a
closer site with the second site somewhat off the back end.)
Kimo KH7U
Message: 1
Date: Tue, 17 Jun 2014 08:29:15 -0400
From: Don Kirk <wd8dsb@gmail.com>
To: qrv@kd4e.com
Cc: RFI <rfi@contesting.com>
Subject: Re: [RFI] Recommended Handheld VHF-UHF Yagi?
Message-ID:
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David,
I should also mention that you might consider a small log periodic antenna
that covers VHF and UHF, but don't know what's available (this would
provide more frequency flexibility with just one antenna). The folks that
I've worked with at Duke Energy use what appears to be a small log periodic
antenna mounted on top of their van for radio direction finding of power
line noise (you can see a picture of this antenna as well as my yagi
antenna on one of my simple websites at
http://sites.google.com/site/powerlinenoise/ if you scroll down toward the
bottom of this website page).
Don
On Tue, Jun 17, 2014 at 8:14 AM, Don Kirk <wd8dsb@gmail.com> wrote:
> Hi David,
>
> For power line noise direction finding I use a portable 4 element yagi for
> use on 136 MHZ AM (I don't currently have AM RX capabilities on UHF). If
I
> had UHF capabilities I would use both a VHF and a UHF yagi. Make sure you
> use the antenna on a frequency it's designed for, as the pattern will not
> maintain itself as you depart from the design frequency (I used EZNEC to
> determine how much longer I needed to make the elements on my 4 element 2
> meter yagi for use on 136 MHZ, and then extended the elements using
> alligator clips).
>
> You should also buy or build a simple 20 dB attenuator that you can
> install between the antenna and receiver as you get close to the source of
> interference, otherwise the signal is often so strong when you get close
> that you can no longer find the nulls off the side of the antenna, etc.
>
> Don (wd8dsb)
>
>
> On Mon, Jun 16, 2014 at 10:06 PM, qrv@kd4e.com <qrv@kd4e.com> wrote:
>
>> I will add it to the list of needs "It will tune 160m through 10m."
>>
>> Right now I need something handheld & directional for VHF/UHF to
>> use with a Pro92 that is on the way here.
>>
>> I have a handheld AM-FM-SW receiver which ferrite-loop is somewhat
>> directional & due to the HF-RFI level has no trouble finding signal,
>> now I need to narrow it down & am told VHF-AM with a small yagi
>> antenna is the way to go.
>>
>> The local utility only has the AM receiver in their truck (useless)
>> and an ultrasonic receiver with a dead & possibly unobtanium
>> battery pack ... so I need to show them the way ...
>>
>> Thanks - David KD4E
>>
>>
>> > David Cole wrote:
>>
>>> I'd build a loop. In fact I am building the loop described here:
>>> http://tomthompson.com/radio/ReceivingLoop/loop.html
>>> Very well documented loop build.
>>>
>>>
>>
>> --
>>
>> David Colburn, KD4E - Nevils, Georgia USA
>>
>> Safe & Secure Search Engine: duckduckgo.com
>>
>> Android for Hams: groups.yahoo.com/group/hamdroid
>> Creative Tech: groups.yahoo.com/group/ham-macguyver
>> Raspi Alternative: groups.yahoo.com/group/beagleboneblack/
>>
>> Restored to design-spec at Heaven's gate 1Cor15:22
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>>
>
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