[Elecraft] P3/K3 spurry

[Fred Jensen]

Somewhere, not too far after the introduction of the P3, Elecraft seems 
to have received some inferior RG-58 patch cables with BNC connectors 
from a supplier and the problems were several.  In my case, at narrow 
spans [20 KHz or so], the baseline would just drift up.  Putting my hand 
on top of the P3 sent it back down where it belonged.  At wider spanss 
[~100 KHz, I could see that it looked like a very broad spur of variable 
amplitude.

Elecraft sent me a new cable with explicit instructions to cut the old 
one into small pieces so it didn't show up at a flea market. :-)  I did, 
the new cable solved the problem.  Anyone who has worked in 
manufacturing engineering knows the problem, sometimes it's 2nd or 3rd 
generation ... your supplier got some bad stuff from their supplier and 
didn't know about it.

It is very important that the case of the P3 be electrically intact ... 
any overspray on contact surfaces be removed and *all* screws tight. 
Also, if you have an early K3 [mine is #642], there is a simple mod to 
increase the first IF output.  Just destroy one SMT resistor ... you 
don't have to unsolder it, just break it with needle nose pliers ... and 
replace it with a "regular" resistor.  Results in less gain requirement 
in the P3, and got rid of a lot of "grass" for me.
73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2014 Cal QSO Party 4-5 Oct 2014
- www.cqp.org

On 4/8/2014 11:09 AM, Bill W2BLC wrote:
> I had problems similar to what you describe when I first got the P3. The
> story is simple: Use a mil-spec RF patch cable between the K3 and the
> P3.