I was asked to post the following info on rfi@contesting.com which I had also posted earlier today on the topband@contesting.com, so here it is. Within the last few months I noticed a raspy signal on
Roger, Not sure what kind of scope functionality you are looking for (just audio or rf???). On my laptop I use a program called sound card scope and it allows you to capture audio waveforms. You can
"Making friendships with our neighbors and helping them with their electronics problems might get us further towards resolution than becoming a RF community organizer stirring up protests and ill fee
Hi Tom, I'm the one that reported the 3 Samsung Plasma TV cases to Ed and the ARRL, and in all cases the common mode chokes were the same (14 turns of a power cord on a 2.4" OD Fair-Rite #31 mix toro
We have a Keurig single cup coffee maker (MODEL B145) at work and it's a very high current device (1500 watt rating which would be 12.5 amps). On a 15 amp outlet circuit that typically uses 14 gauge
Hi Ken, I think you need to take a step back. No matter were you look you will find sources of interference. The question is what source of interference is causing your problem. Therefore the first q
"then it probably isn't noise from an arc on a power line" Power line arcing is often easy to identify by viewing the AM radio audio output on a scope (you typically see spikes at 120 hertz indicatin
HI Paul, Here is a link to a youtube recording of what I hear on 136 MHZ AM using a small handheld scanner (Radio Shack Pro-94) that has the AM aircraft band when listening to power line noise (in th
I previously said "Here is a link to a youtube recording of what I hear on 136 MHZ AM using a small handheld scanner (Radio Shack Pro-94)" By the way if you look at the audio waveform of the noise in
Hi David, For power line noise direction finding I use a portable 4 element yagi for use on 136 MHZ AM (I don't currently have AM RX capabilities on UHF). If I had UHF capabilities I would use both a
David, I should also mention that you might consider a small log periodic antenna that covers VHF and UHF, but don't know what's available (this would provide more frequency flexibility with just one
Cortland (KA5S) said "MY RFI hunting has almost all been with loops or yagis -- and by ear.", and my experience has been exactly the same. What's much more important than an S meter is the ability to
Late last week I encountered interference on 160 meters which was repeating at 41 khz intervals, and this morning I was able to track the problem down to low voltage bookcase lights at my neighbors h
Hi Paul, My 4 turn shielded loop is very simple, and it's based on a design in the July 1977 issue of QST by W1FB (the article was called Beat the noise with a "scoop Loop". My 4 turn shield loop is
Recently noticed an increase in my noise level on 160 meters, and a about 3 weeks ago I tracked it down to a new apartment complex which is located 0.41 miles away. Today I noticed that the signal ha
Oops, the link I provided in previous e-mail was for one of my videos associated with this case. The link to my website is : http://sites.google.com/site/broadbandrfi/ 73, Don (wd8dsb) ______________
This past weekend I encountered interference on 160 meters that I tracked down to a neighbors Nintendo 3DS after market power supply. Full details can be found on a simple website I created to docume
For many years my wife's treadmill caused strong interference on 160 meters when it was in use, and yesterday I was able to completely eliminate the RFI using a combination of two different filters.
Hi Chris, My picture was taken at a bad angle. I actually soldered the green wire coming from the treadmill (load side of the filter) to the case of the filter) as is the green wire on the line side
Hi Ken, May or may not be a related topic, but thought my following info might help you long term. I had been using a filter I built on my phone line that feeds my DSL modem (original filter design b