Bill, If the K3 S-meter is calibrated with the preamp ON, and then ABS mode is set on, the S-meter response for a 50 uV input will be S-7. If one is going to use S-meter ABS, then it is best to calibrate the S-meter for S-9with the preamp off.
Yes, I know what "the manufacturer's instructions" say, but I know how my K3 responds, and I also recall Lyle Johnson's response to this exact situation in his posting of November 15, 2009 in which he said the S-meter must be calibrated for the way you will use it. He in fact calibrates his with the PREAMP and ATTN both OFF and uses the S-meter in ABS mode (just as I do). When calibrated that way, it will not be correct in NORMAL mode if the preamp is ON. In other words, the S-meter will respond correctly only under the conditions for which you calibrated it. You get to decide what your normal operating situation will be - S-meter normal or absolute, preamp on or off and attenuator on or off. I prefer to use S-meter absolute so S-9 indicates 50 uV at the antenna input regardless of whether the preamp or attenuator is on or off. Take your pick. Yes, I believe the manual could be more explicit. 73, Don W3FPR Bill W4ZV wrote: > On Wed, Nov 18, 2009 at 12:09 AM, Philippe Trottet [via Elecraft] < > [email protected]<ml-node%[email protected]> > >> wrote: >> > > >> Dears >> I've seen on the manual S9 /50 microvolts is adjusted with Preamp ON . >> As a new Elecrafter I need some explanations, because with my previous >> rigs, I use to calibrate S9 without the preamp. >> Thanks >> Philippe A65BI >> K3 #3616 >> >> > > Bon jour Phillipe, > > The simple answer is "Always follow the manufacturer's directions". A more > complex one is that the K3, being a DSP rig, compensates internally in > firmware for the fact that PREamp is ON during the calibration procedure. > > I also recommend using CONFIG: SMTR MD - ABS. This will place the K3's > S-meter in ABSolute mode, so that the S-meter always reads the signal being > applied to the input terminals correctly, independently of whether PRE or > ATT are selected internally. This is also different than most rigs but, if > you think about it, it is better since the S-meter always read the true > signal level at the input terminal, before any gain or attenuation is > applied inside. > > 73, Bill W4ZV > > > ------------------------------------------------------------------------ > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 9.0.707 / Virus Database: 270.14.69/2508 - Release Date: 11/17/09 > 02:40:00 > > ______________________________________________________________ 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
