[Elecraft] K3 AGC and Apparent Noise and Signal Distortion

Wed Feb 3 16:20:04 EST 2010

Grant Youngman N5QT wrote:
> 
> Oh, good lord.  This is ridiculous.  "The noise was so bad on my K3 i had
> to go back to my S-38C with external Q-multiplier  just to work the
> contest" ... and on and on.
> 
> With no personal affronts intended, perhaps just learning to use the radio
> would help.
> 

Spot on Grant...doesn't this remind you of Orion a few years ago?

FYI here's a note I got from Rob Sherwood NC0B regarding his experience with
the K3 in the CQ 160 last weekend.  I believe everyone knows Rob is one of
the most objective critics around when it comes to evaluating radios.  My
point in posting this is that we need to consider the source before taking
many complaints at face value.  In most cases, these are reflecting lack of
knowledge of some of the posters more than performance of the K3.  Said
another way, always use some caution when reading comments here or on eHam
(especially if they're from folks who use screen names only and don't have
the guts to post their calls).

##################################################
Hi Bill,

I did post a comment on how the K3 performed.  Using 40 ohm per channel
stereo headphones, I was not bothered by any audio distortion issues.  I ran
the AGC the whole time, and noted no problems.  I am not into the RF gain
back and the audio up method.   I have the AGC setting on SOFT, an option
that came out last summer I believe. 

Due to the QRN on Saturday, I ran the attenuator most of the time.  No use
having the band noise reading up scale a few S units.  I only spent about 10
to 12 hours on the contest, as I was not feeling well on Friday or Saturday. 
Worked 15 different countries and 8 JAs.  Russia was a struggle for me, as I
only worked one, and a few western Europe.  No VKs this time like in W1BB
contest.   Used the K3 about 80% of the time.  Semi-breaking with the Alpha
89 was flawless.  Didn't have some setting right to make it full QSK, not
that I normally run that way.  Will sort that out next weekend.

I had to drop down to 150 Hz BW several times due to adjacent QRM.   The
roofing filter switches in at 400 Hz, but I did not notice any problem with
the DSP between 300 Hz and 150 Hz, not that I expected that to be an issue. 
Key clicks were a problem at times, but nothing fixes that, and I did hear
one station in Idaho that I could copy from his phase noise 1 kHz away on
either side.

73, Rob
#######################################################

Regarding Grant's "S-38C in the CQ 160" comment, below are the current Top
Ten claimed scores (Multiop and Single op) for the CQ 160 CW (IMHO the
world's toughest environment for any receiver).  I've indicated (***before
the call) stations that I know for a fact were using K3s...there could be
others in the list, but I'm sure of these:

http://lists.contesting.com/pipermail/3830/2010-February/191049.html

Call               QSOs StPrv    DX   hr      Score Club
USA Multi-Op HP
***KC1XX             1870    59    80    40  1,154,256 YCCC
K1TTT             1672    59    77    40    967,096 YCCC
***W2FU              1756    58    77    38    936,765 Rochester (NY) DX As
NQ4I              1573    59    82  39.5    829,362 SECC
K1LT              1559    58    75    39    776,587 MRRC
N7DD              1410    59    83    33    752,032 Arizona Outlaws Cont
K0RF              1494    59    74    33    707,693 
AK9F(@WB9Z)       1542    59    75    40    700,418 SMC
***N1LN              1552    58    70  41.5    679,936 PVRC
***W8RT(@W8TOP)      1354    57    74  35.5    622,381 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
USA Single Op HP
K1DG(@N1LI)       1741    59    82    30  1,292,265 YCCC
K8PO              1702    58    76    30  1,185,900 YCCC
***K3ZM              1627    57    81    30  1,095,582 
***K1UO              1441    58    77    30    941,895 
***W4ZV              1542    58    68    30    829,332 PVRC
KU1CW(@N0NI)      1473    59    75    30    803,062 
***AA1K              1405    58    67    30    735,750 FRC
***K5NA              1397    58    71    30    653,901 CTDXCC
W1MK              1285    55    55  18.5    637,560 YCCC
NR5M(NM5M)        1359    58    65    32    595,074 CTDXCC

I seriously doubt many of these folks considered swapping their K3 for an
S-38C!  My point is, when you see ridiculous comments like Grant quoted
above, always consider the source before taking them at face value.  As to
learning the radio, the **current online** manual and errata should be your
first stop:

http://www.elecraft.com/K2_Manual_Download_Page.htm#K3

The following links are also good learning resources with multiple
links/pages in each:

http://www.elecraft.com/K3/K3FAQ.htm
http://www.elecraft.com/K3/k3_operating_tips.htm
http://n1eu.com/  (click K3 link to the left)
http://www.zerobeat.net/mediawiki/index.php/K3_Wiki_at_ZeroBeat.NET

In most cases, Elecraft's default settings are a good starting point.  The
K3 is sort of like having a sports car with automatic everything.  However,
when you're ready to take it to a higher level of performance, the hooks are
there to do so, but you need to understand what you're doing first by
educating yourself.

73,  Bill  W4ZV

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