[Elecraft] KX3: popping noise in radio speaker

[Edward R Cole]

While on my trip in the lower-48 I installed batteries in my KX3 for 
the first time (run it off 13.5v PS in the shack).

I noted that there was a regular popping noise at a regular beat 
about once per second.  I checked battery voltage and saw that is was 
below 12v and dropping slowly.  I used eight AA batteries which all 
tested at 1.53v before installation - brand new out of the 
package.  8x1.53 = 12.24v but there is loading so voltage started at 
about 11.9v.  I noted current was running about 250ma with radio in 
SSB and normal volume level.  I guess the radio draws pretty hard in receive.

I removed the batteries and radio runs normal with 13.5vdc 
applied.  I guess using 2.2v lithium or NiHD batteries would work 
better.  I do not intend to run with internal batteries but wondered 
if anyone else has encountered "popping audio" and is it voltage 
related?  Or is this related to the speaker physical fit issue with 
early models of the KX3?  Mine is SN 475 (kit).

73, Ed - KL7UW
http://www.kl7uw.com
     "Kits made by KL7UW"
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