[Elecraft] K3 PRE function question

[Edward R Cole]

Just my observations on 6m with only the internal PRE on my K3 
(purchased circa 2010):

I noticed a lack of sensitivity on 6m.  I had a ARR P50VDG preamp 
with 22-25 dB of gain which worked better than the internal 
PRE.  That gave me about 12 dB more gain compared with running the 
PRE.  Also lower NF (typ. 0.5 dB).

I then purchased a PR6-10 and that helps considerably over using the 
PRE.  I have used my K3+PR6-10 for copying 6m-eme signals with a 
single yagi (6-element) so that speaks well of the PR6-10.  I use the 
ARR preamp mounted at tower top for eme and it is a little bit better 
(has more gain) on very weak eme signals using JT65.  I use DIGOUT-1 
to control my PR6-10 and use the pass-thru connections for the 
ARR.  That adds nice convenience for using the two preamps.

I have a second smaller 6m yagi which I use the PR6-10, only.  BTW 
this is equal to my KX3 with preamp ON (which says a lot for the KX3).

My opinion is the PR6-10 makes the K3 better on higher bands than the 
internal PRE (which I leave off).  If you are considering getting one 
its a good (if not essential) upgrade for the original K3 on 6m and 
10m.  Yes, you will see a small rise in the noise reading on the 
s-meter (due to more gain), but sensitivity is improved more than 
that (due to lower NF).  I see about S3-4 noise floor on 6m with the 
PR6-10 and S5 with the ARR.  PRE runs maybe S1 (a guess as I haven't 
used it for some time).

73, Ed - KL7UW
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Date: Thu, 30 Nov 2017 07:25:09 -0500
From: Randy Lake <randyn1kwf at gmail.com>
To: Elecraft List <elecraft at mailman.qth.net>
Subject: [Elecraft] K3 PRE function question
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         <CACnmA1PE1UX0MRuU=PtBZaieTUzkxx5tFhMdFcjqxCFPyogKbw at mail.gmail.com>
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This is a pretty simple question regarding the K3 PREamp (not PR6). If I do
not have the PR6 does the PRE on the front panel help with RX on 6m/2m (int
module) or does it merely increase noise?
Thanks


73, Ed - KL7UW
   http://www.kl7uw.com
Dubus-NA Business mail:
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