[Elecraft] External speakers for K3 - A caution

[wayne burdick]

Ken Kopp wrote:

> Caution!  Do -not- plug a mono plug into the external
> speaker jack.  Audio output IC failure will likely occur,
> as a mono plug shorts one half of the IC.

This can only happen if you have CONFIG:SPKRS set to 2. If you set it 
to 1, the right speaker channel is turned off, so a mono plug can be 
safely used.

In addition to this, an upcoming beta firmware release detects the case 
where SPKRS is set to 2, a mono plug is inserted, and speaker volume is 
set to a moderate or high level. (The firmware looks for excess 
receive-mode current drain due to the AF amp IC going into thermal 
shutdown.) If this happens, the K3 will automatically set SPKRS to 1, 
reminding you with a brief flashed message.

73,
Wayne
N6KR


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