[Elecraft] K3 Configuration - No mono plugs in the stereo spkr jack!

[Dave Hachadorian]

Here's another way to blow U1 - turn off the agc and tune across
a very loud signal.

As I have said before, the audio amp should not be this fragile.
It needs better protection.

Dave Hachadorian, K6LL
Yuma, AZ

--------------------------------------------------
From: "eric manning" <eric.manning at engr.uvic.ca>
Sent: Thursday, February 25, 2010 8:25 AM
To: <elecraft at mailman.qth.net>
Subject: [Elecraft] K3 Configuration - No mono plugs in the
stereo spkr jack!

>
> DO NOT, repeat NOT, plug a mono plug into the stereo speaker
> jack on the
> back of your K3.
>
> The manual says that the microprocessor firmware will switch
> the audio
> to SPKRS 1, which it will.
>
> However, if there are other events queued up for the cpu to
> process, it
> may take some milliseconds, during which time
>
> the shorted output may blow the audio amp, which is chip U1 of
> the DSP
> board. {What is the audio output doing on the DSP board instead
> of the I/O board? - but that's
> another story}
>
> You then get to replace the DSP board - like I did  -  which is
> good fun but  a fair amount of effort. And it costs the company
> $.
>
> eric
>
> VA7DZ
>
>
>
> -- 
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