[RFI] S FL Noise help

[KD7JYK DM09]

Like you said, someone may already know, if you hear it, someone else 
may hear it.  If so, that's awesome.  If not...

Lets start with exact frequency (ies), or overall range, then reception 
mode, type of receiver, antenna used, power source, and if wide spread, 
if possible to what extent, a square mile, 20 square miles, limited to 
specific areas?  Is it stronger at any particular spot?  Get some 
recordings to provide to some persons direct as they can't be passed 
through the list.

Some will say RFI can't be ID'd by description, or sound, but those that 
have been around, or even just heard a few types, can do just that, as 
most RFI is unique to a large extent. A switching mode supply is unique, 
the model number of consumer garbage it's installed in isn't, but nobody 
will ever confuse it with the ignition system in a car, or even a power 
line or wireless weather station, so a thirty second recording can rule 
out literally billions of RFI sources across the US.

It may be local to you, may even be your own receiver, or power source, 
or what you're using to move around to hear the signal all over the 
place.  Have you heard the signal on foot, with a battery powered 
receiver, away from everything?  To rule out a receiver, have you heard 
it to the same extent with an entirely different receiver and different 
power source?

Do you have any other electronics on your person at the time?  I've 
heard mobile phones, WiFi, Bluetooth, digital cameras, MP3 players, 
near-field devices, like contactless payment devices, and transponders, 
the type of stuff a person may normally carry.  Even a digital recorder 
I used to use wiped out a large frequency range from HF to UHF, so I use 
an analog cassette recorder to document RFI.

You did mention 440.  Any chance you are listening around 433/434 MHz? 
If so, there is an ISDM (industrial, scientific, data, medical) band 
there, and you will hear noise/telemetry, pretty much everywhere around 
those frequencies, pretty much anywhere in the US.  The devices are 
supposedly limited to 300', but I hear them miles from the source, even 
so far out in the desert, or hills, sources can't be seen.

Any radar installations in your region?  440 is also a military radar 
frequency range, and I sometimes get blasted.  The PAVE/PAWS system on 
the west coast, for example, operates from 420-450 MHz, and wipes out 
individuals, repeater, links, you name it, and I even hear it direct a 
few hundred miles east of it on occasion.  From the late 80's to late 
90's, 420-430 MHz in southern california was often affected by several 
radar systems.

Any extra information can help.

Kurt