Bill, I missed that recent update. It was not that way previously. We have to keep up with the latest developments (and I failed). Wayne and I had some discussion about this a while back, and I was not certain of the outcome - Apparently we now agree.
73, Don W3FPR On 1/16/2011 1:46 AM, Bill Conkling wrote: > I just re-read my manual (rev D7), and it says on pg 51 for s-meter cal if > SMTR MD = NOR, set PREAMP ON. If SMTR MD = ABS, set PREAMP OFF. > > ...bc nr4c > > -----Original Message----- > From: Don Wilhelm [mailto:w3...@embarqmail.com] > Sent: Sunday, January 16, 2011 12:43 AM > To: a...@elecraft.com > Cc: elecraft@mailman.qth.net > Subject: Re: [Elecraft] P3 S meter variance > > Alan, > > I might add about the K3 CONFIG: SMTR MD = ABS, that the calibration > procedure indicated in the manual may (or may not) be the "proper" thing > to do. > The manual suggests that you calibrate the S-meter with the preamp ON. > If you do that, and set the S-meter to ABS, you will find that the > S-meter response is about 2 S-units lower than what you may expect. I > prefer to do the calibration with the S-meter off, and then the response > in SMTR ABS is more what I would expect. > > Since everyone's expectations do not necessarily match mine (obviously, > I disagree with Wayne on this item), you can take your pick - do it the > way the manual says, or do it like I have. The choice is entirely > yours. Like all things S-meter reading related, there is a great > variation between receivers, The K3 has re-vitalized the old Collins 50 > uV equal S-9 "standard". That standard is not a standard at all, and > many transceivers do it differently, but with the K3, you do have a > choice depending on how you want to set it up. If you cannot decide how > you want it, go with the manual instructions - they work and work quite > well. If you deviate, know why you are doing that deviation and know it > is for your own situation, others may or may not make the same choices. > > 73, > Don W3FPR > > On 1/16/2011 12:20 AM, Alan Bloom wrote: >> There are a couple reasons why the K3's S meter and the P3 display may >> show a different level. >> >> As Don mentioned, the P3 will generally show a much lower level than the >> K3 on noise. It's because the effective bandwidth of the P3 is >> generally only one display pixel, about 1/450 of the span. Less >> bandwidth means less noise power in each display point. The same thing >> happens to some extent with an SSB signal. >> >> Another issue is that the S meter reading on the K3 may change when you >> turn the preamp or attenuator on or off. To prevent that happening, set >> CONFIG:SMTR MD to "ABS". >> >> If you do that and calibrate both the K3 S meter and the P3 amplitude, >> then the two should closely agree when measuring a steady CW carrier. >> >> Alan N1AL >> > ______________________________________________________________ > 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 > ______________________________________________________________ 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
