K2 battery leak warning

[Bob Boehmer-2]

I just replaced the battery in my K2 yesterday.  I am pretty sure that
the last time I replaced it was spring/summer of 2007 so I expected to
get more life from it.

When I removed the battery I discovered that the negative terminal and
crimp on connector were badly corroded.  After removing the battery I
could see a small amount of seepage around the joint where the top of
the battery case is joined to the main body of the case.  Fortunately
it was a very small leak and does not seem to have caused any damage
other than corrosion of the negative terminal.

After replacing the battery and the damaged terminal I figured I
better check the voltage that was coming in to the rig.  I had always
set my power supply so the K2 voltage display showed 13.7V as
recommended in the manual.  What I discovered though is that when my
DMM shows 13.7V on the P3 connector on the RF board the K2 voltage
display is only indicating 13.4V.  P3 is after the blocking diode so
the K2 voltage display shoul;d agree.

I assume that over time I cooked the battery and caused the leak.

So anybody who leaves their K2 battery float charging may want to open
up the rig and verify the actual voltage at P3 instead of relying on
the K2 display.  (Or set the input voltage to the K2 to 14.1V to 14.2V
as recommended in the KBT2 manual.)


73
Bob KG3F
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[David Pratt]

In a recent message, Bob Boehmer <[hidden email]> wrote ...
>When I removed the battery I discovered that the negative terminal and
>crimp on connector were badly corroded.

>I assume that over time I cooked the battery and caused the leak.
>
>So anybody who leaves their K2 battery float charging may want to open
>up the rig and verify the actual voltage at P3 instead of relying on
>the K2 display.  (Or set the input voltage to the K2 to 14.1V to 14.2V
>as recommended in the KBT2 manual.)

Bob - Someone may correct me on this, but I believe the original 14.1 to
14.2V specified was when early models of the K2 used an SB530 Shottky
diode for polarisation protection. This was later changed to a 95SQ015
which provided a lower voltage drop.  With that diode I run my K2 with
14.0V at the power input terminals and my original battery lasted for
seven years with no leakage problems.

73
--
David G4DMP
Leeds, England, UK
------


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