K3 - Hi Cur and no speaker output

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K3 - Hi Cur and no speaker output

VE3NFK

Turned on my K3 this pm; and got hi-cur  (mw band, not possible to transmit)
turned off  - checked connections; tried again... one or two times more;
then no hi-cur and still no spkr out.  

Headphones are fine.

menu settings make no difference.

Sounds like my spkr out circuit is fried.

Any suggestions?

Thanks  John VE3NFK
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K3 - Hi Cur and no speaker output

Ken Kopp-3

Hi John,

Could you be using an external speaker / speakers
with mono plug / plugs?

If so, this is a well known audio output chip killer.

If it's the audio output chip gone south it's a bear
to change and not for the faint-of-heart.

73! Ken  - K0PP

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Re: K3 - Hi Cur and no speaker output

VE3NFK
Hi Ken

no - stereo  - and mod done to prevent the short... thanks for the thought...

I can plug the speakers into the front phones plug and they work there...

73  John VE3NFK
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Now fixed - new question Re: K3 - Hi Cur and no speaker output

VE3NFK
Thanks for Dale's telephone help and Gary's email reply.
Got a replacement L4950TS from Digi; and ordered one from Elecraft.

With Dales' advise was able to replace the IC and rig back in operation.

Question:

I have been using amplified computer speakers plugged into the
SPKR output on the K3 back.... as they are not an 8 or 4 ohm load
is it possible that caused the failure?

thanks

73 John VE3NFK
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Re: Now fixed - new question Re: K3 - Hi Cur and no speakeroutput

Dave Hachadorian
Congratulations on replacing that IC! I was too chicken to try
it. I'd like to see the advice you got for replacing it.

The speaker amp is fragile. I have blown it twice by running with
AGC off, AF limiter threshold high, and tuning across a very loud
signal.  It is reasonable that a high-Z load could be a problem,
but I don't know for sure.

Dave Hachadorian, K6LL
Yuma, AZ



--------------------------------------------------
From: "VE3NFK" <[hidden email]>
Sent: Saturday, September 25, 2010 10:17 AM
To: <[hidden email]>
Subject: [Elecraft] Now fixed - new question Re: K3 - Hi Cur and
no speakeroutput

>
> Thanks for Dale's telephone help and Gary's email reply.
> Got a replacement L4950TS from Digi; and ordered one from
> Elecraft.
>
> With Dales' advise was able to replace the IC and rig back in
> operation.
>
> Question:
>
> I have been using amplified computer speakers plugged into the
> SPKR output on the K3 back.... as they are not an 8 or 4 ohm
> load
> is it possible that caused the failure?
>
> thanks
>
> 73 John VE3NFK
> --
> View this message in context:
> http://elecraft.365791.n2.nabble.com/K3-Hi-Cur-and-no-speaker-output-tp5552943p5570295.html
> Sent from the [K3] mailing list archive at Nabble.com.
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list:
> http://www.qsl.net/donate.html 

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