[RFI] 9Khz spacing of intermodes carriers interference

[Jim Brown]

On 1/20/2013 11:05 AM, AMI SHAMI wrote:
> *Any idea what can be the source of this noise.*

I continue to be amazed that new members don't seem to study the long 
history of a reflector like this one before posting questions. The noise 
source is clearly some electronic device with a clock (because it 
repeats at 9kHz intervals), is being radiated by wires (cables) 
connected to that noise source, and picked up on antennas connected to 
the receiver.  The noise source could be the clock in a 
microprocessor-based products (almost any modern product), or it could 
be a switching power supply for anything from a battery charger to a 
wall wart to low voltage lighting to a doorbell.

There is also the strong likelihood that the noise source is in your own 
home, perhaps even within your ham shack.  It is also quite likely that 
one or more Pin One Problems is involved, both in your shack and at the 
noise source.

A good starting point is downloading and STUDYING (not a quick read, but 
reading over and over for deep understanding) of 
http://audiosystemsgroup.com/RFI-Ham.pdf

73, Jim K9YC