[Elecraft] [K2] lack of sensitivity...?

[Don Wilhelm]

Gil,

It is difficult to make a definite answer without some additional data.  
Yes, the atu in the K1 could make some difference, but not an extreme 
difference on receive.

The most likely guess is that you missed a solder connection somewhere 
in the receive section of the K2.  Go over the board with a suspicious 
eye.  The receive portion of the K2 is between the MCIO IC (in the 
middle of the board) and the front panel.

The fact that you have full transmit power on all bands says that the 
problem is *not* in the bandpass filter nor the Low Pass filter.

73,
Don W3FPR

On 8/30/2012 2:03 AM, Gil G. wrote:
> Hello,
>
> I knew this title would grab some attention ;-)
>
> Well, since my K1 worked so well, I decided to build a K2.
> It took me 30 hours over three days. Everything works, but…
>
> First, the receiver is pretty deaf on 20m. Not much static at all, faint signals.
> I plugged in my K1 on the same wire, and what I could barely hear on 20m on the K2 came in full blast on the K1.
> The preamp helps a little, but not much.
> On 40m, the score is closer, but still advantage to the K1 over the K2 with preamp on.
> I can use FL1 and FL2, but with 3, the signal is very attenuated, with 4 (200Hz), usually gone.
> The other bands, I haven't listened enough yet to make a diagnosis… I can hear more static than on 20m.
> I have set the filters as indicated in the manual.
>
> The K1 has the ATU, would that make such a difference?
> I use a 35.5ft wire with 13ft counterpoise, directly out the BNC via a binding post.
>
> By the way, I do get full output power on the K2 on all bands.
> I precisely peaked all bands on receive, then on transmit with my QRP wattmeter.
>
>