KPA has FAILED...high SWR reported by K3 when amp in "Operate"

[ke9uw]

My KPA500 causes a high SWR showing at the K3 when the amp is in transmit operate. All else seems to work ok...reloaded firmware...checked faults...something about "power lost without controlled shutdown".

Any ideas? Pin diode?

[ke9uw]

Hi,
The amp has worked well with 500 watts out, and in standby works fine with 100 watts and the power shown on the led meter is correct. When in operate, it shows high swr with only 1 or 2 watts of drive. So something in the t/r switch has failed.
I guess.
Thanks for the reply.
Chuck, KE9UW

Sent from my iPad

On Mar 14, 2012, at 1:11 PM, "[hidden email]" <[hidden email]> wrote:

> Chuck - I'm a brand new KPA500 owner ...so don't have a lot of history. Probably not this simple, but I would suggest looking closely at the clearance between the center pin of the high power output connector and that metal shield. I thought the design was exceptional but was disappointed at how there was almost no clearance here. (If I had a Greenlee punch, I would have taken a nibble out to provide more clearance!)  It's possible when you kick into high power, it could arc/short or have a bad VSWR.  Also, have all the cables on the output side been run 500W+ before??  73- Mark WA3OFR
> Sent via BlackBerry by AT&T
>
> -----Original Message-----
> From: ke9uw <[hidden email]>
> Date: Wed, 14 Mar 2012 06:37:06
> To: <[hidden email]>
> Subject: [Elecraft] KPA has FAILED...high SWR reported by K3 when amp in
>    "Operate"
>
> My KPA500 causes a high SWR showing at the K3 when the amp is in transmit
> operate. All else seems to work ok...reloaded firmware...checked
> faults...something about "power lost without controlled shutdown".
>
> Any ideas? Pin diode?
>
> -----
> Chuck, KE9UW
> --
> View this message in context: http://elecraft.365791.n2.nabble.com/KPA-has-FAILED-high-SWR-reported-by-K3-when-amp-in-Operate-tp7371793p7371793.html
> Sent from the Elecraft mailing list archive at Nabble.com.
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... [show rest of quote]

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[ke9uw]

Excellent response from service with an RF unit on the way...appeared not to be switching into the transmit mode when in "operate".

[ke9uw]

UPDATE! The new warranty RF unit is installed and works well. Though it proper to let y'all know...

Here is the note I sent to Gary Surrency...

"Hi Gary,

I got the RF unit, installed, and all works well.
Sending the defective unit back tomorrow.
Thanks so much for the excellent service.

Regards,
Chuck, KE9UW"