Your position should be to offer to assist a qualified technician in >isolating and correcting any deficiencies by providing periods of >operating to test the results of any repairs.
I'd say it depends entirely on the attitude of the RFI victiim, and the ham's relationship with that party. The vast majority of RFI complaints today are the result of Pin One Problems in the victim equipment. These are a manufacturing defect that is the result of poor design, and any wiring connected to the equipment will act as a receiving antenna for our signals, where they will be rectified and amplified.
In today's world, "qualified technician" for consumer electronics is an oxymoron.
Several years ago, I helped ND2T diagnose and cure strong RFI to his next door neighbor's "exotic high futility" system, in a living room only 20 ft from Tom's antennas, which were driven by a big ACOM legal limit amp. Tom introduced me as an audio expert and RFI expert (which I am) then returned to his shack and transmitted on all the bands. I stuck chokes on cables until the RFI went away, and by the time Tom arrived after our work was done, had the guy ready to open his wallet to buy them at my cost. Tom, however, insisted on paying for the cores himself. Problem solved.
It is NEVER a good idea to modify the equipment, but it IS good to disable the antennas (that wiring) by adding ferrite chokes tuned to the transmitter frequency(ies). Tuning is accomplished simply by using the "right" ferrite mix and adjusting the number of turns through the core.
Speaker cables are a very common antenna. Another excellent move is to replace parallel wire loudspeaker cables (zip cord, no matter how exotic) by twisted pair. #12 copper makes excellent speaker cable (there's a classic AES Paper by Prof. R. A Greiner, Dept of EE at U Wis about this), and twisting strongly rejects RF coupling. I have solved MANY cases of RFI by doing this.
RFI causes and solutions are covered in considerable detail in http://audiosystemsgroup.com/RFI-Ham.pdf 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
