[Elecraft] K3: Loss of speaker audio after DSP board upgrade

[K4IA at aol.com]

I had the same experience and posted about it a  few weeks ago.  You must 
be very careful to fully seat the pins into the  plugs - all the way!  

A good hint is if the screw holes do not line  up perfectly when you put 
the cover back together, you probably haven't seated  the pins.  It will look 
fine to the eye but if the pins are not pushed in  to the max, you can lose 
audio.

Buck
k4ia
K3 #101

In a  message dated 6/28/2010 5:45:54 P.M. Eastern Daylight Time,  
sjp at sjprior.fsnet.co.uk writes:
I received the upgrade DSP board today.   Swapping over the boards was very
straightforward, but on switching on the K3  I found I had no sound from the
built-in speaker (headphone audio was fine)  unless I had the config option
set to run with headphones and speaker  simultaneously. Therefore neither 
the
connection to the loudspeaker  connection or the speaker itself are at 
fault.
No output from the rear  speaker socket either.

I took it all apart and re-installed.  I  could see no misalignment of
headers anywhere, nothing in fact which was in  any way obviously a fault.
Put it back together again.  Problem still  there.  Then I re-installed my
original DSP board (fortunately I had not  been too hasty in returning it to
Elecraft!) and everything was  fine.

Having assured myself that this was not a wider issue, I installed  the
upgraded DSP board for the third time.  Now the speaker worked, but  flexing
the DSP board slightly (with the left hand side cover removed) could  make
the fault come and go.  Out came the new board again to check for  dry
joints, cracked tracks, shorting metal bushes etc.  I could see  nothing
wrong, although I know that hairline cracks are not easy to  spot.

I put the new board back in for the fourth time and now the K3's  speaker
seems to be reliable again.  I had looked at the mating of the  pins, looked
to see whether there was any dirt there etc., all to no  avail.  I would 
like
to think that I have somehow sorted the problem but  have a sneaking
suspicion that it might come back to haunt me!

On the  topic of the replacement board itself, I can see very little
difference  between it and the Rev B board it replaced, however there is an
extra IC  compared with my previous board. I was expecting a piggy-backed
board  somewhere, but perhaps I have got the wrong impression from reading
this list  about what has changed.  The audio is certainly fuller and easier
on the  ear.


73 Stephen G4SJP

K3  #980




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