Ed, If you read through page 17 of the manual, it explains why the noise floor (base line) changes. This is the same effect you notice when reducing the IF bandwidth on the K3 - a narrow setting will produce a lower s meter reading than a wider one.
The pertinent paragraph is: "The noise level will generally be lower on the P3 display compared to the K3 S meter. The reason is that the effective bandwidth of the P3 is generally one display pixel, which is approximately span / 450. The smaller the bandwidth, the less noise. For example, if the span is 45 kHz, the effective P3 bandwidth is 45,000 / 450 = 100 Hz. If the K3 bandwidth is 400 Hz, it will show a 6 dB (one S unit) higher noise level than the P3." There's nothing wrong with the P3, it's just the laws of physics! 73 Stephen G4SJP On 7 November 2011 17:09, K7WIA <[email protected]> wrote: > I just did a check with the XG3 at -73 dbm it is right on at 100 kc span, > and > it is also right on with in 1 or 2 dbm at 10 kc.. but it is just the base > line that drops.... ? > > Ed K7WIA > > -- > View this message in context: > http://elecraft.365791.n2.nabble.com/P3-base-line-changes-with-span-with-tp6971105p6971189.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > 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
