[Elecraft] k2 kpa 100 speaker problem

[Don Wilhelm]

  Mark,

3 questions in the same post - let me try them one at a time (they are 
not related).

The screws into the heatsink:  Two possibilities exist, 1) the holes are 
not drilled deep enough.  To check, remove a screw and check the depth 
of the bottom of the hole with a 1/16 inch or smaller diameter tool (a 
component lead will do.  The hole should be deeper than the length of 
the screw threads.
2) The hole is deep enough, but is not tapped all the way to the 
bottom.  If that is the case, then the hole can be tapped deeper with a 
4-40 bottom tap (note that is different than a normal tap - a normal tap 
will not do the job).  Thirdly, Elecraft can replace the heatsink if you 
explain and ask at parts at elecraft.com.

No speaker:  Is it possible that you have the speaker wire to the KPA100 
plugged in wrong?  The header is P5 on the RF Board - there is a P5 on 
the top of the Control Board, but it has no audio on it.  Also, 
reversing the wires of the speaker cable in the housing (or at the 
soldered connections) will short out the audio.  The ungrounded wire is 
on pin 1 of P5.  You can remove the K2 bottom cover and check continuity 
between the rear rightmost solder pad of the speaker jack and the pin 1 
pad of P5.  Also check continuity between the center rear pad of the 
headphone jack and the rightmost pad - with the headphone plug removed, 
there will be continuity there if the switch in the headphone jack is 
operating.

Low audio in the K2:  The K2 does not have a lot of excess audio gain, 
but one should not have to run the AF gain all the way up to hear - the 
10 o'clock position should be more than enough for normal levels.  If 
you have to run the audio above the 12 o'clock position, you may have a 
different problem in the receiver.  How does the S-meter respond with a 
50 uV signal from a signal generator like the XG1 or XG2?  It should be 
about S-9.

73,
Don W3FPR


On 1/21/2011 9:42 PM, ve7ymm wrote:
> My new kpa100 looks like its working okay except for the top cover plate
> screw holes not being deep enough.  I guess I will just use some lock
> washers under the 3/16" screws. No QSOs yet but all seems to check out
> according to the specs. However, the headphone jack switch that allows the
> speaker to work quit after about 3 months of use, just like the one on my K1
> did. The speaker doesn't work, nor does the external speaker jack, just the
> headphone jack.  I put in a new one while I had the K2 apart for testing the
> kpa100, and now it still doesn't work.  Any suggestions on troubleshooting
> this?  I might add that the headphone volume seems low to me.  I normally
> have the af and rf gain on all the way.  Should I just give up, and use
> amplified speakers with the headphone jack?
> Mark Mellish, VE7YMM