Ron, you are completely correct - if you can hear the atmospheric noise at all, the receiver will hear signals right down to the noise level. Once that amount of distributed gain is achieved, the next most important characteristic of a receiver is the dynamic range which is an indicator of how strong a signal can be received before the receiver blocks and distorts (reducing the ability to hear weak signals in th evicinity of strong ones).
When I was a young ham (that was back in the youth of SSB), I did get the impression that there was a relationship between how loud the receiver was and how sensitive it was. After some study and some receiver design, and more years of experience, I discovered that those old thoughts relating sensitivity and 'loud' were indeed quite different. One can always add more amplification and make it louder, but making the noise louder is not necessarily a good thing - one must make the signal louder and not the noise to improve the reception of weak signals. If you want an extreme descrition of how a really quiet receiver can sound, Rick Campbell KK7B often has an apt description in his writings about his phasing receivers. 73, Don W3FPR > -----Original Message----- > > I think "failed" is a misnomer. It sounds as if the only receiver in your > comparative tests that is behaving ideally is your K2. > > The last thing you want is excess "front end" gain. All you want is just > enough to bring signal levels up above the internal receiver > noise and then > have the bulk of the gain *after* the i.f. filters where only the > signal of > interest is being amplified. > > The K2 exhibits that characteristic, as you observed. On the lower > frequencies no pre-amp is needed. The band noise easily over-rides any > internal receiver noise. But on 10 meters it does not until you > turn on the > preamp. That means the K2 does not have excess front end gain on the lower > bands that will limit its dynamic range. > > It sounds like the receivers you're using to compare the K2 with have a > less-than-ideal gain distribution. > > -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.432 / Virus Database: 268.16.12/628 - Release Date: 1/15/2007 11:04 AM _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
