I may have found the cause of the anomalous HI CUR warning in **receive**
mode, thanks to my big orange Maine coon cat, Mr. Opie.  In rubbing his chin
on the VFO B knob while I was listening last night, he rotated the control
to the 12V DC bus voltage display, which I then noticed was oscillating
between 13.6 V and 12.7 V.  When I checked the DC bus current display, it
was oscillating between 0.4 A and 2.1 A - clearly something was amiss. 

Tonight I checked the terminal voltage on my Astron RS20-A linear supply,
and found it to be stable at 13.7 V with no load (K3 turned off), but then
it dropped to 13.4 V with the K3 'on' in receive mode.  I again checked the
K3's internal volt/ammeter readings and found the same periodic oscillation
in each one.  Curious to know if the oscillation was due to an interaction
with the supply regulator, I swapped out the RS20-A for my Astron SS-30
SMPS, which I normally use with my K2/100 setup.

Lo and behold, the DC bus oscillations ceased!  

I have not yet spent enough time listening using the alternate power supply
to know if the HI CUR warnings will also cease, but will do so over the
coming week. Fortunately, I don't have to watch the K3 display because the
HI CUR condition also reduces headphone audio substantially, which gets my
immediate attention.

Kudos to Mr. Opie for his uncanny sense of what might reveal a potential
cause of the spontaneous HI CUR warnings in receive mode.

73,
Mike, K8CN



--
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