[RFI] Noise sniffer article in QST - WW3S
Thu, 24 Jan 2002 08:39:26 -0600
N4ZR is correct in suggesting an AM receiver in the aeronautical band.
One of the nicer professional models made for Utility Companies and
Cable Companies to use in policing noise was manufactured by Oak
Industries in Illinois and used a frequency of approximately 260MHz
and employed an S meter to measure noise intensity. It also used a
small 5 element yagi hand carried that would alow the operator to
rotate the antenna through both horizontally and vertically polarized
What makes N4ZR's suggestion so worthwhile is one could easily use a
small yagi as the sniffing antenna with the handheld receiver.
Typically the noise is easier to find when the sensing equipment
operates on higher frequencies than 150MHz based on my long personal
experience in locating it. Remember noise is basically an infinite
number of squarewaves usually very broad spectrum.
The Oak unit referred to above with its yagi antenna allowed the
operator to identify exactly where the noise was coming from on a pole
for example. Often times due to cracked insulators, loose clamps or
ground wires etc.
Good luck in locating your source.
J. Leon Pringle, Jr W 5 N A