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
>> _______________________________________________
>> RFI mailing list
>> RFI@contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
>>
>
>
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|