David N. wrote:
Hello all. I just installed the KBT2 battery kit in my
K2. I have a 5 watt unisolar flex panel
Same setup here.
The design of the KBT2 does not regulate voltage - it just regulates a
small current to float charge the battery. It's specifically designed
for an external, approximately 14 volt supply.
If you want to charge the 2.9 AH battery up fast, by all means you can
connect it directly to the PV panel, but you must monitor the battery
voltage as it will try to climb very high. The voltage must be
regulated - a common method is to use a small charge controller such as
the Micro M+ from SunLogic (owned by a ham)
(http://www.seslogic.com/microm+.html) or Don Brown (I think that's the
fellow - he offered it here again just in the last day or two).
My older Micro M is external - I used one of the transverter holes to
add a coaxial jack, clearly separated from the main power, that runs
direct to the battery. The charge controller has to bypass the resistor
and diode included in the KBT2 kit and see the battery directly. I've
heard that others have added the Micro M internally to the K2 lid, but I
haven't seen one.
Some hams also have used a zener diode to clamp the voltage down. This
means, however, that the zener must dissipate the excess power, and may
get warm. I've never tried this method.
Hope this helps.
--
73,
Mike Boice, KW1ND
Karns, TN
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