On Tue, Feb 24, 2015 at 12:27 PM, Wayne Burdick <n...@elecraft.com> wrote:
> Jim (et al), > > The K3's audio has improved due to three factors in the past couple of > years: > > - a low-noise, low-pass audio filter stage was added to the DSP board, > eliminating high-pitched CODEC artifacts > Approximately what serial number introduced this change? Thanks. 73, geo - n4ua > > - DSP firmware changes were made to correct AGC linearity and eliminate a > CODEC quantization problem > > - main MCU firmware was modified to allow the user to select the lower AF > cutoff in CW mode (100/200/300 Hz) by adjusting the lower edge of the > crystal filters > > With the above changes in place, we carefully measured the K3's audio > spectra and compared it to other radios with the same type of class-AB > final AF amplifier IC (most transceivers fall into this category). They are > all virtually identical. > > Rob, too, told us that the audio spectra he measured on a recent K3 (with > new synths and the latest DSP and MCU firmware) was significantly improved > from the K3 he measured several years ago. > > While it is possible to reduce audio IMD products even further, this > typically requires a class-A final audio output stage, which would add > perhaps 0.5 to 1.0 amps of additional receive-mode current drain (and an > associated heatsink). That is inconsistent with the K3's intended usage, > which includes excellent power efficiency for portable applications (Field > Day/DXpedition/travel). Also, most users would not notice such a subtle > change. > > 73, > Wayne > N6KR > > > On Feb 24, 2015, at 8:19 AM, jim <jbol...@outlook.com> wrote: > > > Wes, > > > > I agree, and if you look at a post I made a couple days ago, it states > that. > > Sherwood also states his list is sorted on one column and people shud > take > > all factors into account when choosing a radio. > > > > I would NOT recommend a K3 for it's audio. > > > > Each person has their needs and should review them carefully. I would > also > > not recommend a Drake R4-C, even though it is in the top quartile. > > > > I will send you a copy of an earlier post that I made. > > > > > > Jim > > W6AIM > > > > > > > > -----Original Message----- > > From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of > Wes > > (N7WS) > > Sent: Tuesday, February 24, 2015 6:12 AM > > To: elecraft@mailman.qth.net > > Subject: Re: [Elecraft] Sherwood Engineering Tests > > > > I'm sure there's a point here and I just fail to see what it is. > > > > Rob has stated many times (look for his videos) that one number does not > a > > radio make. In fact, as best that I know, he doesn't own a K3. > > > > Wes N7WS > > > > On 2/23/2015 11:01 PM, jim wrote: > >> Guys, > >> > >> Further, pesky, facts on said Real Radio at > >> http://www.sherweng.com/table.html . > >> > >> Number two on the list. That is out of 116 receivers listed on the > >> Sherwood page. > >> > >> That puts said Real Radio in the top 3% of the radios Bob Sherwood has > >> tested for a critical receiver performance parameter. > >> > >> BTW, you will have to use the "Page Down" button, more than twice, to > >> even get a hint of the Kenwood 590. It is number 20 on the list, > >> putting it in the top 17% > >> > >> Also, important to note, is the Drake R4-C with the Sherwood roofing > >> mod, listed at number 28. The R4-C is *ONLY* > >> 45 (forty five) year old technology and that puts it in the top 23%. > >> Yep, FORTY FIVE year old technology. Yep, top 23 %. > >> > >> Just some further, pesky, facts......................... > >> > >> Rake > >> > >> P.S. BTW, I learned 45 years ago. This flies in the face of > >> someone's comment that I never learn. > >> > >> Ho Hum, another pesky fact............. > >> > >> > >> > >> > >> > >> > > > > ______________________________________________________________ > > 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 > Message > > delivered to jbol...@outlook.com > > > > ______________________________________________________________ > > 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 > > Message delivered to n...@elecraft.com > > ______________________________________________________________ > 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 > Message delivered to n4ua...@gmail.com > ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
