"But this RFI stuff is not enforced unless it interferes with important 
stuff"

RFI is not as simple as "off or on". The issue can be quite complicated. The 
consumer electronics industry generally tries to get away with the cheapest 
stuff possible. If you remember the Radio Shack TRS-80 computer of the 
1980's aka "Trash 80". This was one of the biggest generators of RFI ever to 
hit the consumer market. Then there are some products that are 
electronically "naturally noisy" and there is not much you can do about it.

The commercial two way radio market this is much more regulated and built to 
little higher standard. But you are dealing with consumer electronics in 
nearby homes that are built to the cheapest standards that will allow 
unwanted interference in the system and then home owners demand the 
commercial user clean up the mess that the home owner actually created 
themselves. If you have twenty feet of speaker wire from your home stereo 
running near the front of your home this will act like a receiving antenna 
and sometimes pick up a two way radio be used in a car driving near by. If 
you have an external FM antenna with a cheap consumer receiver you can 
expect that now and then you are going to get hit with "10-4 good buddy"

In the 1980's there was a big push to get the consumer electronics industry 
to better engineer their disposable junk to prevent interference from 
legitimate amateur and commercial users. At the time it was estimated that 
it would have cost about a few cents extra per radio. The industry raised 
hell and nothing was done.

Getting into the commercial stuff. When you have a large radio site with 
multiple antennas, radios, circulators and duplexers you are going to have 
problems. This is why setting up these systems can be an engineering 
nightmare. But if done correctly interference within the site will be 
minimal. The problem being nearby by with cheap consumer radios that have no 
filters. This could be hell on earth.

When all is said and done it is the end users to be aware of their own 
problems and take prudent action to add by pass capacitors, ferrite beads, 
and be careful of where they run the speakers and telephone wires. If there 
is an illegal radio interference issue then this has been be dealt with, but 
when complaining you have to be sure your own operation is technically up to 
standard.

Here is one self imposed RFI issue: I knew of an electrician who had the job 
to run the housing wiring and speaker wiring for an upscale home. The idiot 
ran the speaker wiring right next to the AC lines. The 60 Hz hum made the 
high end entertainment system was useless.

I have spent a lot of time dealing with this. This issue gets real ugly very 
quickly. I like discussions about this issue, the more people know the 
better people can react and solve problems.

Jim

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