[Top] [All Lists]

Re: [RFI] RFI Digest, Vol 203, Issue 15

To: Wes Stewart <n7ws@yahoo.com>
Subject: Re: [RFI] RFI Digest, Vol 203, Issue 15
From: Michael Martin <mike@rfiservices.com>
Date: Thu, 12 Dec 2019 10:50:03 -0500
List-post: <mailto:rfi@contesting.com>
Everyone has their own opinion,
So here's mine!
I use ultrasound on almost a daily basis. Usually when people have a difficult 
time utilizing a source on a pole it's because they're on the wrong Pole. using 
RF to locate the source is highly recommended and a must.
Also keep in mind that ultrasound units such as the mfj is very insensitive but 
using an ultrasound device such as the radar engineers model 251, Which has 
probably three times the sensitivity level of the mfj, can produce very good 
results. Again it's only as good as the previous step so if you haven't 
verified that the structure you're looking at contains the source you may not 
be at the source structure there for the results will be poor with the next 
step. I use ultrasound with about a 95% success rate. Even when I cannot 
determine the source when using the ultrasound, I can usually determine what it 
is because the ultrasound doesn't work.
As for the union issue, I've seen a couple of inputs concerning that and the 
fact is there are Union rules and regulations that limit who can do this, not 
just a safety standard.  Unions determine, in a lot of companies, who can do 
what job and high voltage is an area where they often regulate. The hot stick 
line sniffer that is used on the end of a hot stick is extremely functional and 
100% successful. The hotstick line sniffer has an RF detector that works at 114 
megahertz as well as ultrasound that is 43 kilohertz. Both work well but may 
only be used by people qualified to work in the primary zone or within the 
minimum approach distance.

On Dec 10, 2019, 6:22 PM, at 6:22 PM, Wes Stewart via RFI <rfi@contesting.com> 
>I'm friendly with the RFI sleuth with our local electric coop (also a
>ham).  He tells me that ground level ultrasonic sniffers are pretty
>worthless.  Any physical obstruction attenuates the signal, according
>to him.  They do use one but on a hot stick where it can sniff up
>close.  Unfortunately, it's a union shop so he can't do it and has to
>have a line crewman do it.  The logistics of this are really
>detrimental to efficiency.  (Unspoken opinion of unions goes
>Wes  N7WS
>Date: Tue, 10 Dec 2019 17:47:18 +0000
>From: David Eckhardt <davearea51a@gmail.com>
>To: Rfi List <rfi@contesting.com>
>Cc: "Bascombe J. Wilson" <jay.wilson@vodec.net>,    Terry Bullett
>    <tbullett@skybeam.com>,     Ted C <hm55555@hotmail.com>, Greg Ella
>    <gregella53@gmail.com>
>Content-Type: text/plain; charset="UTF-8"
>Use of an ultrasonic detector is highly useful in finding discharges on
>electric distribution grid, especially localized to the home
>Sure, MFJ makes one, but there is an option I ran across on the AirSpy
>group.  if you have a Discovery (or R3 modified HF+) from AirSpy, you
>an ultrasonic receiver.  Have a view of the following link:
>            https://youtu.be/H8z02pICisM
>Dave - W?LEV
>RFI mailing list
RFI mailing list
<Prev in Thread] Current Thread [Next in Thread>