The XG3 is not generating the 60 Hz hum you are hearing if it is running off its battery. On its fundamental freq and harmonics, the radio will hear it as an unmodulated carrier.
It is common to hear 60 Hz hum when listening to another transmitter in the same room, typically due to RF coupling to the mains power lines. Also if you are powering the XG3 off of an external supply, you may have a 60 Hz ground loop between it and the radio. 73, Eric WA6HHQ On 4/21/2011 12:03 AM, Edward R. Cole wrote: > Wayne, > > I connected the XG3 directly to my sub-Rx via the aux ant and the > signal is a clean CW note. I did a quick calibration check at 14.020 > with -73 dBm and s-meter reads S-8 so pretty good (uncalibrated since > I got the radio a year ago). I did another test transmitting 0dBm > thru the air and can see that it is 60-Hz hum from something (I hear > the CW note in there). I checked for ripple on my bench PS and see > nothing at .005 with the scope. It ran for about half an hour with > no detectable drift in the tone frequency. That is impressive > considering the K3 has the K3EXREF. > > I wanted to report back so that my earlier report was not seen as a > negative about the XG3. BTW be careful switching to -33 dBm into the > K3 it really clears out the dust in the speaker. Running -107 dBm > shows S-2 (36 dB less than S8). That really shows off the linearity > and accuracy of the K3 s-meter. I set up all the recommended > settings for receiver sensitivity measurement. > > Later I will connect my Sinader meter to do a S+N/N measurement on > 28-MHz (my freq of interest as IF for 2m and 1296 transverters). Be > interesting to compare with the internal audio meter in the K3. I > will also compare the XG3 with my 1296 signal source. > > XG3: very nice! > > Ed - KL7UW > > ------------------------------ > > Message: 44 > Date: Wed, 20 Apr 2011 17:30:30 -0700 > From: Wayne Burdick<[email protected]> > Subject: Re: [Elecraft] XG3 Arrived > To: "Edward R. Cole"<[email protected]> > Cc: [email protected] > Message-ID:<[email protected]> > Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes > > Ed, > > You should not hear a hum or buzz when listening to the XG3 on a > receiver. The fact that's it's not a sinewave doesn't mean that it has > audio-frequency modulation; it is a pure carrier. You might be hearing > 60-Hz pickup due to the lack of a common ground, etc. > > Wayne > N6KR > > > > > > 73, Ed - KL7UW, WD2XSH/45 > ====================================== > BP40IQ 500 KHz - 10-GHz www.kl7uw.com > EME: 144-1.4kw, 432-100w, 1296-testing*, 3400-winter? > DUBUS Magazine USA Rep [email protected] > ====================================== > ______________________________________________________________ > 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
