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PA temp reading problem


Donald Whiteman
 

For several days now the PA temp reading has been starting out at a higher and higher level when my K3 is first turned on. While the FP temp might read 25C, the PA temp would start out at a significantly higher reading and has now drifted to over 100C when the K3 is turned on even after being off for a couple days. Since this is well above the 84C cut off level of the KPA3’s protective circuitry, as expected, the KPA3 amp will not operate at all. I have tried the Config menu PA temp adjustment, but it can only lower it a few degrees. The FP temp readings behave perfectly normal. When I have operated my K3 over the years the PA temp might have reached close to 45C, but that’s about it. I am guessing that maybe the PA temp sensor on the KPA3 heatsink has failed in some way and that I will have to send my K3 in for repair. Any thoughts? Thanks.

73, Don KK9H


David G3YYD
 

Don

 

Take out the PA and the adapter between it and the main board. Give the pins a wipe with some cloth or tissue. Put them back in. Recheck if that does the job you are good to go.

 

If not then suggest contact Elecraft support for assistance.

 

73 David G3YYD

 

From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Donald Whiteman via groups.io
Sent: 21 July 2020 14:22
To: Elecraft-K3@groups.io
Subject: [Elecraft-K3] PA temp reading problem

 

For several days now the PA temp reading has been starting out at a higher and higher level when my K3 is first turned on. While the FP temp might read 25C, the PA temp would start out at a significantly higher reading and has now drifted to over 100C when the K3 is turned on even after being off for a couple days. Since this is well above the 84C cut off level of the KPA3’s protective circuitry, as expected, the KPA3 amp will not operate at all. I have tried the Config menu PA temp adjustment, but it can only lower it a few degrees. The FP temp readings behave perfectly normal. When I have operated my K3 over the years the PA temp might have reached close to 45C, but that’s about it. I am guessing that maybe the PA temp sensor on the KPA3 heatsink has failed in some way and that I will have to send my K3 in for repair. Any thoughts? Thanks.

73, Don KK9H


Donald Whiteman
 

Hi David, 

Thank you for your suggestion. I did that yesterday and when I put everything back together and turned it on the PA temp was still reading over 100C. I also made sure all the screws were tight on the KPA3, which they were, so I guess I am going to have to send it in for repair. I should also mention that the fans immediately go to their highest speed as they should with that high of s PA temp reading.

73, Don


Thomas Doligalski
 

Wonder what your current draw is, right at startup?

If it’s normal, I would presume it’s the temperature sensor. 

Tom W4KX

 

On Jul 24, 2020, at 10:18 AM, Donald Whiteman via groups.io <kk9h@...> wrote:

Hi David, 

Thank you for your suggestion. I did that yesterday and when I put everything back together and turned it on the PA temp was still reading over 100C. I also made sure all the screws were tight on the KPA3, which they were, so I guess I am going to have to send it in for repair. I should also mention that the fans immediately go to their highest speed as they should with that high of s PA temp reading.

73, Don


Donald Whiteman
 

Yes, current draw is perfectly normal as is everything else about the radio. Only the PA temp reading has gone haywire. I’ve been in contact with Elecraft support and will be sending it in as soon as they send me an RSA. Thank you everyone for your thoughts on this.

73, Don KK9H