I think the noisy issue derives out of our quite old analog listening habits and expectations.
I would estimate for easily half of the reflector population (my real guess is 75%), that their listening to radio career began with an analog HF radio that didn't have enough gain to present ambient antenna noise over receiver noise except on the lowest bands. Without exception, these were tube radios whose circuits didn't flat-top overdrive, just round it off, and whose audio transformers' response gradually died over 4 khz. There were no sudden transitions in any of them save the few lucky enough to have a crystal filter for narrow reception on CW. As another has stated, the sharp limits of selectivity, vast extents of audio response, and enough receiver system gain to bring anyone's 10 meter outside ambient noise up to full audio, were ideals, frankly just not attained, or in some modern radios curiously avoided (knew something?). Quite a lot of posted complaints here had at their roots one single issue: on the lower bands, a typical metropolitan area RESTING outside ambient noise level is S2 S4 and S8 on 40, 80 and 160 meters. In the K3 attenuator off, preamp on, and RF gain at full results in ambient noise fully engaging the AGC and remaining at full audio on 160 through 40 and possibly on 20 as well. If RF gain is full, and preamp is on, the receiver is set to present a quarter microvolt as full loudness, and anything higher than that REDUCED to full loudness. This means that outside ambient noise on 160 will always be at full loudness, and also at full "shrill" given the wide audio response. This was the first complaint about our contest group's first exposure to an Orion, and for all practical purposes the ONLY one. Nothing in second or third place. Once we knew we had to PURPOSEFULLY REDUCE the receiver gain (settings for preamp, attenuator, RF gain) for the lower bands to reduce the outside ambient noise to 1/4 full volume, the Orion became imminently superior to the MP's we were using at the time. This remains true with the K3, even though some stubbornly continue to insist they shouldn't have to reduce the RF gain. With the Orion, those settings (including the RF gain) could be remembered by band. Many Orion users will tell you that the RF gain, once set moderately for their locale's ambient noise per band, is never touched again. In effect it was "calibrated" to their local noise. Remembering ATT and PREAMP by band is close to the Orion's flexibility. On my K3, to set 160m ambient noise in a 500 Hz bandwidth to 1/4 audio, I have to turn off the preamp, turn on the attenuator, and reduce RF gain to 2 oclock. Then it's just as quiet as my ancient tube analog receiver. The discussion about fatiguing audio becomes a completely different subject, once proper reduction of gain to match ambient noise is taken care of. 73, Guy. On Sat, Jan 9, 2010 at 8:08 AM, R. Kevin Stover <rksto...@mchsi.com> wrote: > I suspect that's about it in a nutshell. > People have gotten used to listening to a certain level and quality of > noise from the YaeKenIcom crowd that when presented with a receiver this > good they are convinced it's "noisier". Noise, which used to be covered > up or attenuated by phase noise or other crud in the other rigs isn't in > the K3. > > People simply haven't been hearing true reproductions of band noise > etc... with the other rigs. > > My own pet theory. > > Al Lorona wrote: >> So what you are saying is the K3 is too quiet for its own good, and that's >> what makes it so noisy! >> >> >> >> ----- Original Message ---- >> From: "Joe Subich, W4TV" <li...@subich.com> >> To: d...@w3fpr.com; Al Lorona <alor...@sbcglobal.net> >> Cc: Elecraft Reflector <elecraft@mailman.qth.net> >> Sent: Fri, January 8, 2010 8:46:21 PM >> Subject: RE: [Elecraft] RX Test (long) >> >> >> >> However, the stopband also has >> many leakage products (DAC artifacts) in the stopband some >> of which are as much as 50 dB ABOVE the noise floor. >> >> While these products are well below the desired audio in the >> passband, they are "in the clear" as far a local noise. >> This requires the ear/brain system to subconsciously work >> to reject (filter) the undesired discrete frequency products. >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> > > -- > R. Kevin Stover > > ACØH > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
