Re: SWR issue on KPA500


Colin Smithers
 

Elecraft can help you with one of those - ring the helpline and ask for a long weight.

 

From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Ray Maxfield via groups.io
Sent: 27 August 2020 16:40
To: Elecraft-K3@groups.io
Subject: Re: [Elecraft-K3] SWR issue on KPA500

 

I know I will get Hate mail…….

How did you get your License with that statement ?

(Don’t know what the “put a 50 ohm load on it” means though.  What would I be looking for?)

Contact you Elmer for Help………. Ray WA6VAB

 

 

From: David Bunte
Sent: Thursday, August 27, 2020 1:34 AM
To: Elecraft K3 List
Subject: Re: [Elecraft-K3] SWR issue on KPA500

 

Ken -

 

I have a K3 à KPA500 à KAT500 à a remotely tuned antenna. When I am on the air I either use the KAT500 to match my antenna, while the remote tuner at the antenna is in bypass... OR I have the KAT500 in bypass and match my antenna with the remote tuner. I NEVER use both the remote tuner AND the KAT500 at the same time. Do I correctly understand that is what you are doing? I don't have an MFJ1788, but from what I read, it should tune to 40 meters automatically, so an additional tuner in the shack would be superfluous. As a first step, I would suggest you put the KAT500 and the KPA500 both into bypass and make sure the '1788 presents a low SWR to the K3s when running 10 watts. If not, the problem is in the antenna. If it works OK that way, then raise the power to the 53 watts that you normally run but without the KAT500 and see if the problem persists. 

 

The suggestion to "put a 50-ohm load on it" means to replace the antenna with a 50-ohm dummy load. If the problem goes away, then you know the problem is in the antenna or remote tuner.

 

I realize you have gotten several responses. I hope one of them helps you figure out where the problem is so you can get back to having fun on the air.

 

73 de Dave - K9FN

 

 

 

 

 

 

 

 

 

 

 

On Thu, Aug 27, 2020 at 2:39 AM kenneth_yaw via groups.io <kenneth_yaw=yahoo.com@groups.io> wrote:

Sure.  I can give that a shot.

Don’t know what the “put a 50 ohm load on it” means though.  What would I be looking for?

 

73,

Ken

KN7AW

 

From: Elecraft-K3@groups.io <Elecraft-K3@groups.io> On Behalf Of DF9TS via groups.io
Sent: Wednesday, August 26, 2020 12:48 PM
To: Elecraft-K3@groups.io
Subject: Re: [Elecraft-K3] SWR issue on KPA500

 

Loop in  a separate SWR meter between KPA and KAT?

 

(Some years back I had a strange K3 fault, K3 ATU reported high SWR. In reality ATU was faulty. Found that with external SWR meter) 

 

73

 

Gerd

 

On 26. Aug 2020, at 18:44, Gerard <scanneg@...> wrote:

 

Put a 50ohm load on it

 

On Wed 26 Aug 2020, 17:41 kenneth_yaw via groups.io, <kenneth_yaw=yahoo.com@groups.io> wrote:

 

My setup, I believe, is pretty straight forward:  K3s à KPA500 à KAT500 à Alpha Delta Delta-4 à MFJ Super High-Q remote tuner à MFJ-1788 Magloop.

I’m working FT8 on 40 meters at 53 watts.  Have been for a while.  Lately, the KPA500 has been reporting high SWR and giving me a hard fault, automatically switching over

to bypass.  The K3s, KAT500, and the remote tuner are reporting the SWR between 1.5 to 1.7 through the night.  OK for summer.

Could that be the SWR coming back from the KAT500?  All the way from the antenna?  I’m not sure where to begin working on my diagnosis.

 

73,

Ken Yaw, KN7AW

 

 

 

 

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