It's the 4th harmonic Sent from my iPhone
On Apr 24, 2011, at 3:35 PM, David Guernsey <[email protected]> wrote: > I don't have the problem on the 2nd or 3rd harmonic of 3579 KHz, but do on > have > a tone between about 14.316 and 14.318 MHz. > > 73s de Dave KJ6CBS > > > > > ________________________________ > From: Jim Wiley <[email protected]> > To: Grant Youngman <[email protected]> > Cc: [email protected] > Sent: Sun, April 24, 2011 1:11:44 PM > Subject: Re: [Elecraft] 14.316 help! > > > > Grant et al - > > > This is no mystery - it just seems like one. 14.316 (or 14.317) Mhz is > the 4th harmonic of 3.579 MHz, the common color burst frequency. Color > burst crystals are used in an incredible variety of consumer devices. > These days, the oscillators are usually configured as a digital gate > oscillator (read - square wave) that is very rich in harmonics. If you > take the time to look, you will find signals at all the harmonics. We > notice it mostly on 80, 40, and 20 meters because that is where we have > efficient antennas and receivers optimized for reception on those same > frequencies. > > > Is this a problem? You bet it is. Are these devices in violation of > the part 15 rule that says that such devices may not cause interference > to licensed services? Yes, they are. However, there is a fly in the > ointment. The FCC's rules for interference mitigation say that > (paraphrasing here) "It's not interference until someone complains!" > Unfortunately, the burden is on you (the ham) to identify which device > is causing the problem, and then notify the device owner that his gadget > (TV set, computer, stereo set, alarm clock, microwave oven, kids toy, > calculator, FAX machine, treadmill, coffee maker, video game, . . . . . > ) is causing interference. They you get to educate the consumer, an > always interesting endeavor. So, unless you have complained to the FCC > and the manufacturers and the stores that sell the devices and the end > users, it's not interference! Ain't that great?! > > > The process of informing the miscreants will keep you entertained for > some time. Thank you local congress critter for failing to enact more > rigorous standards concerning interference from consumer devices. They > are the ones who responded to the lobbyists from the electronics > industry that promised this would never be a problem, and voted to water > down the rules accordingly. > > > Have a nice day. > > > - Jim, KL7CC > > > > > Grant Youngman wrote: >> I've had a weak 'carrier' in this spot for years. Used to have to endure it >> for >> the Icom Net at 14.317 in the old days. No clue what it is. >> >> >> Grant/NQ5T >> >> Sent from my iPhone >> >> On Apr 24, 2011, at 2:29 PM, Fred Jensen <[email protected]> wrote: >> >> >>> Mine is at 14317.00 and is moderately weak. I >>> >> _ > ______________________________________________________________ > 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 > ______________________________________________________________ > 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 ______________________________________________________________ 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
