Elecraft KXBC3 - Manual

1
Elecraft
®
KX3
KXBC3 NiMH Battery Charger and
Real Time Clock
Installation Instructions
Revision A 2, October 19, 2012
Copyright © 2012, Elecraft, Inc., All Rights Reserved
Introduction
When the KX3 is equipped with an internal battery using eight AA size NiMH cells, the KXBC3 allows
charging the battery from an external 13.8 VDC supply without removing it from the KX3. The KXBC3 also
provides a Real Time Clock and 24 hour alarm that will automatically power up the KX3.
The internal battery powers the KX3 whenever the external power source is removed, or any time the external
power supply voltage falls below the internal battery voltage. Although any type of AA size cells may be used
for the KX3 internal battery, only NiMH cells rated at 1900 mAH or greater may be charged with the KXBC3.
Installation involves opening the KX3 as if you were changing batteries and then using a screwdriver to remove
the KX3 battery retainer and replace it with the KXBC3 module.
CAUTION
The KXBC3 module and many components inside your KX3 may be damaged by
Electrostatic Discharge (ESD) simply by touching them or a circuit board containing
them unless you take specific steps to prevent such damage. See Preventing
Electrostatic Discharge Damage on page 5 before opening the package containing the
KXBC3 module or working inside your KX3.
Specifications
Battery Compatibility: NiMH type batteries with a capacity of 1900 mAH or higher.
Read Charging Batteries on pg 3 for important safety information before charging batteries!
Charging Current: 200 mA
Charging Temperature: 0º C to 40º C.
External Power Supply: 13.8 V at 500 mA for receive only when charging; approx. 3 amperes when
transmitting and charging.
Real Time Clock: Time of day (hh:mm:ss) with 24 hour alarm that will wake up the KX3 if
power is off.
Clock Holdup Time: ≥ 5 minutes. Allows changing the internal batteries without losing time or
alarm setting. The clock continues to run during this time.