200 mhz interference

[Moose]

This happens on different brands of radios when I connect to an outdoor discone. I program 225-250 MHz into a search, but end up having to lockout most of the frequencies due to open carriers. I turned off my computer, cable modem and router but the interference persists. Some signals are strong, 3bars, others are 2 and 1 bars. Two years ago the electric company upgraded their lines running directly from a sub-station to the local pharmaceutical company. These lines run the length of my street. Also, I live across the street from a railroad line. Could any of this be the cause of my interference? I've only monitored the Public Service bands the last several years and never noticed it on them.

 

[scannermanner1]

It's hard to say! I get a lot of RFI in that range too ! I mostly get the interference when im Mobil.....it could be power lines since we have a lot of them above ground.

 

[SCPD]

200mhz

From 200-220MHZ I hear the parkway system its a ker-plunking sound,is that what you are talking about?
if not,you may have intermod....Are you near any cellphone towers or live close to a city?
Im in Clifton and dont see anything of what you describe.
I am a ham and use the 222-224.995mhz for monitoring only.(local repeaters and such)

I once had an issue where there was a metal balloon stuck in a powerline this was causing massive hash,look up!

 

[rbm]

Some switching power supplies put out a lot of 'hash' in that range AND at half that frequency range in the Air Band.

I use POE switches for my surveillance cameras and one of them puts out so much RFI that I have to unplug it when I want to monitor Satcom and air band frequencies.
(It's a recent addition and I've been trying to find a better power supply for it.)

Rich

RFI in Air Band caused by switching power supply.
The yellow band was with that POE supply plugged in and it disappeared completely when I unplugged it.
Right now, the cameras take priority over monitoring those frequencies but eventually I will find a better power supply for it.

 

[prcguy]

Could be cable TV leakage. Check for TV audio on 227.75, 233.75, 239.75 and 245.75Mhz.
prcguy

 

[SCPD]

CCTV

I have a CCTV and it screams all over 440MHZ.
LOL!