"rijo101" wrote in message
...
Hi Group , I have a problem with my home computer and or monitor
generating noise that is picked up on my HF ham radio rig . In order to
cancel the generated noise , how might be the best way to ground or
choke out the noise directly from my home PC ? I presume I first need to
determine the frequency of the unwanted noise signal and then build a
balun or a choke to ground or cancel the noise, maybe !!!
One thing is for sure , the problem exists when the computer is on
and it generates harmonics that interfere with HF radio on Amateur Radio
Frequencies .

This is a tough problem because, generally, the noise is radiated from the
computer circuit boards. The waveforms in computers are rich in harmonics,
thus there is no easy way to filter the noise out. However, you can try:

1/ Physical separation between the computer and the antenna. (Sometimes a
simple reorientation of the equipment can help.)
2/ Is your antenna feedline coaxial? If so, a balun at the antenna can help
(this is because balanced currents in the coax helps to prevent the shield
from acting as an antenna).
3/ Use separate ac supplies and line filters.
4/ Use ferrite decoupling cores on all of the computer leads.
5/ Replace long leads with short leads.