[Elecraft] K2 receiver issues during contest?

[Bill Coleman]

On May 30, 2006, at 10:10 AM, Darwin, Keith wrote:

> On 40 CW, there were some strong signals to my 28' vertical.  30-40 dB
> over S9 was not uncommon.  I noticed with one of these stations, I  
> could
> hear "clicks" up and down the band for +/- several KHz.

It is quite possible that this guy had clicks. The K2, as designed,  
has excellent rejection of adjacent signals. Sure, you'll have some  
cross-over from nearby adjacent signals, but the results are way down  
from radios costing thousands more.

> All of the signals were strong.  K2 doesn't do this as a rule on S9
> signals.  In fact, this is the first time I've noticed it so I'm going
> to say that signals 20 dB over S9 don't produce it (I'd have to double
> check that though).  This makes me think it is an issue with only very
> strong signals.

You'll definitely notice more of this adjacent signal problem on  
really, really strong signals.

> Narrowing the IF filter helped.  Engaging the attenuator helped.

If turning off the preamp or adding the attenuator eliminates the  
clicks, most likely the are being generated by overloads within the  
K2. These must be EXTREMELY strong signals to do this.

> So does this sound like normal fare for the K2 or does it sound  
> like an
> issue?

I didn't have this problem with my K2 this weekend, but I may not  
have tuned across the same signals you did.

Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr at arrl.net
Quote: "Not within a thousand years will man ever fly!"
             -- Wilbur Wright, 1901