[RFI] N6CW TVI

[Tom Rauch]

Hi Dave,

> If you haven't installed a LOW PASS filter on your radio 
> equipment, now is
> the time to do so. .

You may have missed this, but he operates six meters and has 
channel two RFI. Short of a helical resonantor or cavity or 
other very loosely coupled very high Q filters, there isn't 
anything that will stop channel 2 spurious from a six meter 
rig.

>Also, you need to investigate your station ground system

Station grounds are great for lightning and safety.

If a station ground fixes or seriously changes RFI, you have 
a serious antenna system or equipment issue. With a good 
antenna system having low levels of common mode on the 
feeder and good connector integrity in equipment.... an RF 
ground does nothing at all. It would be much better to 
figure out why the equipment needs an RF ground and fix that 
problem than to band-aid the system with patches.

One common misconception is filters have to route unwanted 
RF to ground. That isn't how they work. What they really do 
is block harmonics by adding a series of high impedance 
series components and low impedance shunt components to the 
line. While harmonics are reflected back to the source, they 
remian INSIDE the coaxial line. Anything you do on the 
outside of the coax has no effect, unless you have a bad 
shield connection someplace. Better to fix the shield 
connection than band-aid the problem with grounds.

Checking the coax is excellent advice.

73 Tom