Re: SWR meter problem on K3

Bob McGraw - K4TAX

Yep, all of this testing using the K3, the VNA, and Dummy load would seem to point to a coax jumper being used for each test is likely at fault.   Could be a PL-259 of which the "new good looking" ones are exactly that "good looking".  I have found machine tolerance errors, poor machining, poor plating, not to mention poor installation of connectors.   And I have found that finger tight for a PL-259 is not good enough. I always snug with a pair of 4" Channel Lock pliers.


Bob, K4TAX

On 12/21/2019 4:48 PM, Wes Stewart via Groups.Io wrote:
So you guys are totally ignoring the dummy load comments?

Wes  N7WS

On Saturday, December 21, 2019, 12:00:58 PM MST, Ray Maxfield <wa6vab@...> wrote:

I Agree  WA6VAB 


Sent from Mail for Windows 10


From: Dave Cole
Sent: Saturday, December 21, 2019 10:42 AM
Subject: Re: [Elecraft-K3] SWR meter problem on K3


Hi Lawrence,


Assuming your data is correct your antenna has an issue...  Here is why...


1.  The K3 shows 5:1, tests K3, antenna, and feedline.

2.  The VNA shows 5:1, tests the feedline, and antenna.


I am assuming you had your VNA connected to the antenna or tuner...  If

so, then the K3 is out of line, and you still show 5:1, hence the

antenna or feedline is at fault.


73, and thanks,

Dave (NK7Z)

ARRL Volunteer Examiner

ARRL Technical Specialist

ARRL Asst. Director, NW Division, Technical Resources


On 12/21/19 9:39 AM, Lawrence Stringer via Groups.Io wrote:

> Recently I reverted to usin g my K3 over my TS890S.  However, when I

> turned on the K3 and keyed up, the SWR meter showed SWR  greater than

> 5:1. I suspected the cabling so checked and changed all that, checked

> the antenna on my VNA and still over 5:1.  So, I got out my DMM and

> after measuring my dummy load as 50 ohms, I connected it and guess what,

> still over 5:1 SWR.


> Has anyone else had this problem and if so what was the solution ?


> Thanks in advance,


> Lawrence   G4GZG





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