"The more you turn RF GAIN back, the higher the S-Meter will read."
Well, that's the way it should work, but I can assure you that with my K3 with the factory default RF Gain calibration, turning the control counterclockwise from max would cause the S-meter to increase at first, then *decrease* and then increase again as the control reached minimum gain. That is why I've said repeatedly, NOT ALL K3s BEHAVE THE SAME WAY with respect to RF gain and AGC. If you do not have a 50 uV signal source and you haven't run the latest variant of the RF Gain calibration routine, then you are at the mercy of the default settings. This endless discussion of the "proper" way to adjust your RF gain, attenuator, preamp, et cetera is pointless when there is this variation. Look at Jack Smith's analysis here: http://www.cliftonlaboratories.com/elecraft_k3_and_manual_rf_gain_control.htm and pay particular attention to the chart of gain reduction v. control volts. To be sure, this is a simulation, but Jack is a smart guy and his lab measurements to back this up are second to none, plus I asked someone at Elecraft whether this was accurate and the reply was, "pretty much". Now introduce into this FET characteristic variations that are---well---variable, such as Gm having a 2 to 1 tolerance, and you should be able see how easily one radio can be different from another. Wes N7WS --- On Fri, 12/18/09, Bill W4ZV <btipp...@alum.mit.edu> wrote: Bill W4ZV wrote: > > > 4. Now adjust the RF GAIN knob counterclockwise until the antenna noise > on the meter just stops flickering on the meter. This will be familiar to > OTs since this is the way we set RF GAIN many years ago on analog radios. > Someone just questioned this step. I didn't mean the S-meter should read ZERO. I meant that you decrease the RF GAIN setting until the noise level on the S-meter stops flickering. For example if your noise is flickering S4-5 (as mine typically is on 160m), turn RF GAIN counterclockwise until you get a steady S5 with no flicker. The more you turn RF GAIN back, the higher the S-Meter will read. 73, Bill -l ______________________________________________________________ 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
