[Elecraft] K3 Receiver Performance

[GW0ETF]

Chris,

I don't have a tx antenna for top band but my doublet was piling 'em in on
receive; it was an opportunity therefore to give the K3 receiver a good test
and your signal, being fairly local and a K3 was interesting to listen to.

I was particularly interested in key clicks. I noticed recently that the K3
cw waveform had a very sharp trailing edge and was told that this had crept
in after a 'very recent' firmware upgrade and will be fixed. I knew you were
there +/- 250 Hz (with the filtering down to 50Hz/250Hz 8 pole roofing
filter) but by 'ticks' rather than clicks and you were LOUD; generally the
signal sounded excellent here. Presume you were using an amp and I seem to
recall you may have an Acom 1000 which seems very good with respect to relay
timings (better be - I have one :-) so perhaps the residual ticks *are* down
to the K3 trailing edge which hopefully will be sorted soon.

I agree with you about the filtering. I could search out a weak signal
within about 250 to 500 Hz of a booming eu and wind down the filtering and
could copy the weak signal with no sign of spurii or breakthrough (assuming
no key clicks...!). I'm not so sure about the 'dual pass band' filtering; I
assume this uses the wide (2.7 KHz) roofing filter in order to accomodate
the wide skirts and often when I switched it in the wanted signal would
suffer from agc pumping from adjacent inaudible stations.This fitted with
the way the S-meter reacted and disappeared when the 'normal' narrow
filtering was reinstated.

One thing did surprise me and that was the AFX. Set to binaural and the
filtering out wide I was surprised to find that loud slightly off freq
signals would appear to drop in strength in the headphones when I switched
in the AFX. This was quite unexpected and very marked and had the effect of
bringing up the wanted signal; I can't see a physical reason for this to
happen so maybe it's 'all in the mind' but nonetheless very effective. It
seemed like the unwanted signals were being sent to the 'back of the hall'
when you switched in the AFX and keeping the wanted sigs right in the front
row.

I've had my K3 a few weeks now and I'm still being surprised about it's
performance and features; the more you become familiar with it, the better
it gets.

Have fun,

Stewart Rolfe   GW0ETF (K3 145)




G3SJJ wrote:
> 
> A summary of what is to follow - "Wow!!!"
> 
> This radio was designed and advertised as a contesters radio and it 
> certainly meets all the requirements. Ergonomics are excellent, all the 
> necessary controls are well placed and what's more, work! I spent 
> sometime in CQWW 160 CW this weekend, not a competitive entry with 406 
> Qs, 27 States and 50 countries but enough to assess the K3 rx. The 
> general sound has already been compared to the "Drake R4B" sound. Yes. 
> Very comfortable to listen to. The AGC constants are perfect, at least 
> for me. The Width control coupled with Shift gives a very flexible 
> selectivity selection and the Noise Reduction really eases help my power 
> line noise problem.
> 
> This morning around sunrise when the band peaked it was great to hear 
> the W5s booming in, it was fantastic to be called during a run of 
> Europeans by W6XI in Arizona, but the crunch came in the last hour or so 
> at W2,3,4,8 sunset. The band was packed full of Eu, ranging from s7 to 
> 40+over 9, and yet when I screw the width right down I can copy and work 
> Stateside. Now, these condx are very similar to say 40m in CQWW CW and  
> the K3 came through without a hitch.
> 
> This is real radio, real contesting with a real contester's K3.
> 
> Thanks Aptos !!  Chris G3SJJ
> _______________________________________________
> Elecraft mailing list
> Post to: Elecraft at mailman.qth.net
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
>  http://mailman.qth.net/mailman/listinfo/elecraft    
> 
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
> 
> 

-- 
View this message in context: http://www.nabble.com/K3-Receiver-Performance-tp15125875p15131737.html
Sent from the Elecraft mailing list archive at Nabble.com.