I do have one of MFJ's Model 856, it operates at 135mhz. I have been able to
narrow down rfi sources to a specific pole with it. In fact I used it in a one
block long ally with about 8 poles all giving readings on their lines, and was
able to not only find THE pole, but also determine that it was the transformer
on that pole. Another time I was able to determine which house it was coming
from when standing at the base of a pole that was feeding 6 different houses. I
also found it could point me in the right direction along a line of widely
separated poles along a main street.
It works as good as the MODEL M330 Mini RFI Locator 320-340 MHZ unit my power
company guy uses. However neither his nor mine can tell if the noise we are
hearing is the one that is causing my hf rfi problem. An ac hum like rfi buzz
is
an ac hum like buzz, like comes from dang near all of these poles. Now after 3
frustrating (to me and them) years of hit and miss unnecessary 'fixes', which
has the utility company griping about how many multiple thousands of dollars
they have already spent on my problem(s).
This time, hopefully it will be different, at least I now have them considering
that the problem may even be, as much as, a mile or more from my qth. Not just
with in a 1-2 block simi industrial (shopping center) area and the included sub
station.
This year's chase has been documented on: http://www.k5oai.com/rfi/
warning it's a long (3 page) confusing read. If you skip ahead to page 3, it
starts showing some hope of being resolved. I have another promise for the 1st
week of April for the next step by the utility company.
Actually there are also several other intermittent rfi sources that I am
dealing
with, but the main one I'm after is the power line one that gives me an S9 to
S9+ noise floor from 160m through 40m. It then starts to drop on 20m where it
is
down to an S6-7, and by 10m it's down to an S3.
I get that one fixed and I will be able to find the others on my own. I know
one
is in a nearby house. I call it my summertime noise as it only goes active when
the temps are in the 80's and up. Then there is the winter time one that I
believe may turn out to be from a light in one of the near by parking lots.
Are we having fun yet?
GB & 73
K5OAI
Sam Morgan
On 3/29/2011 3:13 PM, Alan Robinson wrote:
> I have also tried locating with the MFJ Model 852, dipole only, power line
> noise detector. This has not worked well for me. I would like to try their
> Model 856 with the built in 3 element beam. Perhaps this would work well to
> get within a few poles of the source. But I believe you really need to use
> 440 to 450 MHz to get "the pole".
>
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