Subject: Safe Simple Battery Charger

This a safe, simple way to CHARGE a car battery or deep cycle
battery using your ham radio power supply.  Now you can have your
Old battery / Emergency battery always ready for when you need it
to use in event of power failure due to weather or other emergency,
I leave mine on all the time.  

The draw when the battery and Power supply are equalized is minimal
with most tail lights.  You will not notice the "trickle" of current
that is charging your battery while using your radio.

All you need is a 12 volt 3 amp power supply or more Direct current
(Should be 13.8 actual) or you could make one to use with this circuit
with a transformer, Bridge rectifier or diodes, filter capacitors 
and so on.

This circuit also provides  you with a "seat of pants" indication of
charge rate visually using glowing lamp.  Very bright lamp means the
battery is either very dead or charging at high rate.  Dim glow means
almost charged and no light means battery fully charged.

Regarding the Lamp chosen, you can vary the charge rate by using a
higher wattage rating bulb -- 12 watt, 18 watt and so on.  Want more
charging rate?  add a second bulb in parallel or higher amp bulb if 
your power supply will handle the higher charging rate. (Try a Car 
head light for example--but be sure to change diode/ fuse also).

All these parts are "junk box" stuff.  




           5 AMP  50 PIV      (L)  12 volt Automobile
           FUSE   5 AMP       +-+  Tail Light & mounting
                              | |
(+)----->>--+F+------>|-------+ +------->>----+        
                                              |        
                                              -  (+)   
12 volt                                      ___       
Positive                            12 volt   -        
                                 Car Battery ___       
                                      to      -        
 POWER                                be     ___       
 SUPPLY                             charged   -        
                                             ___       
                                              -        
                                             ___       
Negative                                      |  (-)   
                                              |        
(-)----->>------------------------------>>----+