There s a possible clue. Unbalanced connection between computer and rig. Pin 1 problem in computer sound card for sure, probably also in rig. Also the IR drop problem in the cable shield, but that wo
not but I took the CAT5 twisted pairs of telco wire that unused in the 6 pair trunk line running between the barn and house (1,000ft) and terminated them to ground at both ends of the line. My thinki
That is a very common, and very difficult one to fix, because 6 meters (50 - 54 MHz) is right next to Channel 2 TV (54-60 MHz). For a different reason, 6 meters is also difficult for lots of telephon
I've just posted a new version of my tutorial on RFI, Ferrite Chokes, Baluns, and audio for hams. It has the same filename as the original, but the title shows Rev 1, 25 Jul 07. The new stuff is prim
Sorry. http://audiosystemsgroup.com/RFI-Ham.pdf Jim _______________________________________________ RFI mailing list RFI@contesting.com http://lists.contesting.com/mailman/listinfo/rfi
Paul, Thanks for recounting your experience. It's input like this that can save a lot of us a lot of trouble, and help others figure out what's going on in another system. One important correction. I
There are very good and very bad. My 99 Volvo S80 had NO problems. The computer in my 2006 Toyota Sequoia locks up with 100W on 20M. One of these days I'll have time to try to fix it. 73, Jim Brown K
The RFI problem with the Sequoia is VERY likely a problem with lousy (non-existent) chassis bonding, thanks to more concern with paint than bonding. My ohmeter tests showed that almost nothing is bon
This is good advice, not only for the hood, but for every connection between elements of the car's body. And I would do it on both hinges, not only one side. 73, Jim K9YC ____________________________
The "need" for grounding a radio is another one of those widely repeated myths. We DO want a good bond of the shield of coax to the body AT THE ANTENNA, we DO want the DC power pair (preferably TWIST
Belden 1311A and 1313A are sold as loudspeaker cable. Gepco (a very good Chicago company) makes a #12 twisted pair loudspeaker cable. The insulation is not rated for mains power, but would be fine fo
Don't rule out the possibility that it could be a noise-maker in a home or office near you. Examples include battery chargers (for power tools, mobility scooters, etc.), power supplies for consumer e
Every powered loudspeaker I've ever seen has had RFI, especially to VHF. It's a combination of lousy shielding, bad circuit layout, and pin 1 problems. You can fix the pin 1 problems with ferrites. T
Hi Bill, I hope that some list members will be able to make it to the fall AES in NYC, where I'm doing a tutorial lecture on RFI. Oct 8, 3:30 - 6:00 pm. Also, Henry Ott is leading off with a Master's
A 2M/440 talkie, Nextel phone, and Blackberry used as a signal injection probe around the device and its I/O wiring are very effective. It might be worth owning a 6M talkie so that one could use it t
Nuvistors ARE tubes. See http://en.wikipedia.org/wiki/Nuvistor Jim Brown _______________________________________________ RFI mailing list RFI@contesting.com http://lists.contesting.com/mailman/listin
smoke and CO alarms. You could always just remove the batteries. :) Seriously though -- are they completely stand alone, or are they wired into anything? If wired, try a capacitor on the order of 0.0
I have no issues with my IBM T-series laptops running in close proximity to my HF antennas. I don't use an external keyboard or mouse with them (I'm happy with the built-in pointer). Jim K9YC _______