Interference caused by what?

[KC6ZBE]

I've had my station set up at this place since 2007 and never had a single problem. I have a 3 element Mosley mini beam for 10-15-20m and a dipole for 40m...

Lately, I have been getting this annoying noise on 40 meters with the dipole. Using the 20m band with the beam isnt as bad, but I can hear the noise there. Here is the strange thing. At exactly 11pm CST, the noise will just shut off completely. BAM! It is gone. Not sure when it starts up but I have heard it at 7am. We dont have anything that runs on timers and I just dont understand why all of the sudden it is doing this.

My only thoughts are this. We have new neighbors that moved in next door and we have yet to meet them. We never see them, they never come out. Found out the guy owns some kind of IT company and works out of his house. Could this be "networking" noise?

I noticed this noise starting around the end of December. I created a video and posted it on YouTube so you can hear what I am hearing and maybe have an idea as to what it is...

http://www.youtube.com/watch?v=2uTc8W0JZWs

Thanks
Dave

[WX7G]

The signal occurs about every 30 kHz. I suspect is it 1080/30 HDTV from a neighbor's HDTV, possibly a plasma TV. It would seem his TV show ends at 11 PM.

[KC6ZBE]

Thanks for the reply.
Ive heard several different videos on Youtube that show plasma interference but this one sounds a little different so I really didnt know if it was or not.

11pm on the dot when it all disappears is what is odd....

[WB4BYQ]

This does not sound like plasma tv rfi,  i at one time lived near 3 plasma tv's one being about
40 feet from the home.   this sounds like a bpl system or some type of data transfer.  one thing
about rfi and the source,  you cannot be for sure what the source is until it is found.  following the part 15 rules, this rfi is harmful to radio communications,  i would try to rdf the source with a radio on batteries and use the rf gain to point to the right direction.  you could rdf with the kenwood and the beam using the rf gain on the receiver. i have done this many times in my former neighborhood.  if indeed the rfi is coming from the new neighbor you will have to ask him to for his help.  the arrl has a very good person that can help with the case and his name is Mike Gruber at the ARRL RFI desk.  to solve the problem, the source will have to be located.  use your thinking hat to have a plan.  rdf the best direction, take the radio with a battery and short wire outside around your house using the rf gain and att to vary the received signal and move thru your area, and if you approach his house and the rfi goes up in strength then the location must be that house.  there are letters that can be printed to help with the understanding of what is happing with the rfi and your licensed station.
richard   WB4BYQ

[KC6ZBE]

My dipole (the antenna that I get the most noise on) runs directly north and south between mine and the suspecting rfi causing home....During the day, the S level on 40m will still be 10-20 over but the sound isnt as bad as it was in my video....

The only portable radio I have is a Hendricks PFR-3 qrp rig that has 40-30-20m....However, it has very narrow filtering so I dont know if it will work for this....I could give it a shot...

My other problem is that I live in an HOA neighborhood and I am not supposed to have antenna's up to begin with...The only reason I have gotten away with it this long is is that they are not visible from the street and the rest of my neighbors dont really care that I have them up....It would suck if I find out this guy is the RFI offender and he goes to the HOA about my antennas...

Dave

[WB4BYQ]

you may try a Timewave ANC-4 noise Canceller with a small sense ant to pickup the rfi and
phase the noise to cancel inside the ANC-4.  i have used one for a couple of years with about
85 percent success.  MFJ makes one  the 1026 and that unit works as well.  i sold the mfj unit to another ham and he has had success in cancelling rfi in his neighbor hood.  if the rfi does wipe you out from operating, maybe you can scope the guy out and see what his feelings are.

the rfi either is coming thru the ac power feeding his house and into yours as well.  try using a very short ant at you station and see if you hear the rfi. antenna maybe two to three feet long.  place ant near the power outlets inside you house to see if you hear the rfi.

does the rfi cover from say 3.5 mhz to 30 mhz, can you hear the rfi between the ham bands, if so then this sounds like bpl broadband over powerlines try adapter.  these units are supposed to be notching out the amateur bands per the homeplug allance agreement with the arrl on part 15 rules.  maybe show some interest in the other guy with his computer equipment and ask him what does he do with it.  does the rfi appear when he is not at home, any pattern?
maybe a ham from the local area can help with the problem.


ii

[KC6ZBE]

does the rfi cover from say 3.5 mhz to 30 mhz, can you hear the rfi between the ham bands, if so then this sounds like bpl broadband over powerlines try adapter. 

I'm starting to wonder if this is what it is....I didnt know that one can buy a BPL adapter kit, plug it into the wall, and have internet throughout the house....BPL was never used in this area and all of our utilities are underground....

The neighbor could quite possibly have installed a new LCD TV that has some sort of "internet hookup" to stream movies on and such and opted to use a BPL adapter....

The noise starts at around 5.500 mhz and starts increasing as you work your way towards 40 meters....The AM broadcast bands and the 160m portion aren't affected....Neither is 80m....

Thanks so much for your input on helping me with this issue...

Dave