A while back I uploaded a file to the KX3 Yahoo Group giving the percentage 
charge remaining by KX3 voltage display, and suggested charge times.  This was 
based on the Sanyo datasheets for the Eneloop XX (I also uploaded both Eneloop 
XX and 2nd gen Eneloop (2000mAh) to the files section).  I found in practice 
that the chart was quite inaccurate.  I think this was due to I**2R losses in 
the battery pack spring clips, and battery leads. These losses in spring-clip 
battery packs have been documented by other hams.

To update the figures, I partially discharged my KX3 Eneloop XX internal pack, 
then removed the batteries and put them in a battery analyzer.  Knowing what 
their actual remaining capacity was, I then took another look at the Sanyo 
chart, and scaled the results to the datasheet.  My pack was discharged to the 
60% remaining capacity level, so I am very confidant for that data point.  I'll 
have to repeat the experiment for other levels of remaining capacity to confirm 
the new table.  

I removed the old table from the files section of the KX3 Yahoo Group and 
uploaded the new one.  If you don't want to join that group (I certainly 
understand why) email me and I will send you the PDF file.    

Remember, you must measure the voltage of the internal pack when it is under 
load at the 5w CW level--just going by the internal pack voltage when the KX3 
is in receive will give you a very inaccurate number.  To confirm this, I made 
both measurements and found the battery voltage in RX would change by .1 VDC 
vs. the voltage under TX would change by .3 VDC during a single 1/2 hour 
measurement period.  

To answer the flames I will get (again):  1.  No, this data is not in the 
manual.  2.  Yes, I specified measurement UNDER LOAD.  3.  For 2nd-gen Eneloops 
(2000mAh) I suggest reducing the charge times by 20% as a starting point, since 
that is the approximate difference in capacity.  

If you are unsure of the charge time to specify, aim high.  If you aim too 
high, the KXBC3 will terminate the charge when the pack gets warm.  Also be 
sure your source voltage to the KX3 is high enough.  It should be 13.8 VDC or 
higher.  

73  Eric WD6DBM  
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