[Elecraft] 14.316 help!

[David Guernsey]

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 <jwiley at alaska.net>
To: Grant Youngman <nq5t at tx.rr.com>
Cc: elecraft at mailman.qth.net
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 <k6dgw at foothill.net> wrote:
>
>  
>> Mine is at 14317.00 and is moderately weak.  I 
>>    
> _
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