[Elecraft] Sudden KpA1500 power reduction

[Frank Scolaro]

Happened to me several months ago...  one LDMOS out! same symptoms.  You need the power with such great band conditions...

GL
Frank, W2YK




-----Original Message-----
>From: rocketnj at gmail.com
>Sent: Feb 21, 2021 12:23 PM
>To: 'Dana Roode K6NR' <dana.roode at gmail.com>, 'Elecraft Reflector' <Elecraft at mailman.qth.net>
>Subject: Re: [Elecraft] Sudden KpA1500 power reduction
>
>Just my guess is one of the LDMOS devices let out the magic smoke? 
>Just a thought...
>
>Dave wo2x
>
>
>-----Original Message-----
>From: elecraft-bounces at mailman.qth.net <elecraft-bounces at mailman.qth.net> On
>Behalf Of Dana Roode K6NR
>Sent: Saturday, February 20, 2021 9:16 PM
>To: Elecraft Reflector <Elecraft at mailman.qth.net>
>Subject: [Elecraft] Sudden KpA1500 power reduction
>
>I'm in the ARRL CW contest this weekend and the KPA1500 has been working
>fine.  However, a few minutes ago I noticed I was getting about half the
>output power on 20 meters that I typically get with around 30 watts drive
>(about 600w vs 1200w).  PA current is less than normal, around 30a.
>Similar problem on the higher bands, I can no longer get 1000w.  On 40m I
>can, but it requires more drive.
>
>Seems like something died in the amp; I'm not familiar with the design, but
>perhaps an output module.  No errors or ill behavior from the amp other than
>the loss of power.
>
>I will contact Elecraft support unless there is something I'm missing here.
>I just looked in the archive and see that this has happened to others....  I
>use the amp remotely so I guess I'll have to take it home with me.
>
>  Dana
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