[Elecraft] [K3] High internal noise level

[Bill W4ZV]

Pete Smith N4ZR wrote:
> 
> I guess my analog roots are showing - I have grown up used to running RF 
> gain full on, and turning off AGC when I had to ride the RF gain.  But I 
> notice that, as in an analog radio, the S meter is effectively disabled 
> when you turn the RF gain down very far.  I guess I can live without it.
> 

The S-meter can actually help to set RF Gain correctly.  After you determine
the lowest gain setting of ATT/Off/PRE which gives band noise with an
antenna connected and RF Gain max CW, then adjust RF Gain CCW until the
meter holds just above visual noise peaks.  The meter still works for
signals above the noise floor you've just set.

Another point I forgot is to do the RF Gain Calibration on the K3 Utility
Calibration page.  In fact, the best order to do everything is:

1.  RF Gain Calibration.
2.  S-meter Calibration.
3.  Set Rf Gain max CW and set ATT/Off/PRE for lowest gain option that still
gives band noise.
4.  Back off RF Gain CCW so meter holds just above noise peaks.
5.  The K3 stores ATT/Off/PRE settings per band, so you don't need to do
this every time you change bands if you set it up ahead of time (although
multiple antennas per band will necessitate some adjustment).
6.  Set AF Gain for a comfortable listening level on a medium signal
(typically 9-10 o'clock).
7.  If you then let AGC do the work, you probably won't need to touch AF or
RF Gain much in normal operation.

73,  Bill

P.S.  The K3 hears well if you set it up correctly.  Some anecdotal evidence
is below (all from 160m and Diversity also deserves some credit):

http://lists.contesting.com/archives//html/3830/2009-02/msg01298.html
http://lists.contesting.com/archives//html/3830/2009-12/msg02168.html
http://lists.contesting.com/archives//html/3830/2009-12/msg02145.html
http://web.jzap.com/k7rat/2009_Stew.htm (3-way tie for most QRPs)
2010 ARRL DX SOSB160 - 5 QRPs in EU and most DX QSOs, including multiops who
had the added advantage of Packet.
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