here is how to add more storage power to your ka500 or similar device.
have you ever wished that your crank radio had a bigger internal battery? do you want more radio play time? more flashlight time? more battery capacity that is charged from the wall or usb or solar? want to get more cell phone charges before you have to AC recharge or USB recharge or, heaven forbid, crank ?
well here is an idea for you that is simple and adds up to 4 times more battery capacity in some cases. all that is involved is adding a couple of insulating circle shaped pieces of plastic and a couple of short wires. you can decide to solder or crimp the connections, ... whatever you are comfortable with.
Step 1: Step 1 ...
for step 1 you can cut out 2 circles of insulating plastic from a clamshell or 2 liter bottle or similarly stiff and relatively thick plastic. the circles should be the same or slightly larger then the diameter of the throwaway batteries. in my case they were AA size. at the same time cut and strip the ends of a red and a black piece of wire that are both about 3 inches long and of similar or larger gauge to the wires already on the internal battery of the device so it can carry the same amperage safely.
Step 2: Step 2 ...
WARNING!!!: BE ABSOLUTELY CERTAIN THAT YOUR ORIGINAL BATTERY IS THE SAME TYPE OF CONSTRUCTION AND VOLTAGE AS THE BATTERY YOU ARE ABOUT TO MAKE !!! DO NOT MIX BATTERY TYPES!!!
i will be adding 3 X 2000mAh nickel-metal hydride batteries to my radio compartment that match the published information about my ka500 radio original rechargeable battery. the manual states it is a 600mAh Ni-mh battery and we can see it is 3 cells in a wrapper and plugged into a socket.
as we see on the back photo, the battery compartment has springs and plates to hold the batteries in place. YOU MUST CAREFULLY DETERMINE WERE TO PLACE YOUR PLASTIC CIRCLE INSULATORS TO PROPERLY MAKE THIS MODIFICATION AND TO ISOLATE YOUR NEW BATTERIES FROM THE RADIO METAL CONTACTS THAT LEAD TO THE CIRCUIT BOARD!!!
often it is easy to visually confirm the path of electricity that would flow when the batteries are installed. you can often see the metal connectors imbedded in the plastic of the radio and the route they take to the next battery and so on. it is often easy to see where the final terminal is and also where the first terminal is. THIS IS WHERE WE WILL INSERT THE PLASTIC INSULATOR CIRCLES SO THAT THE BATTERIES DO NOT TOUCH THE FINAL OR THE FIRST TERMINALS OF THE RADIO.
your goal is to make the new batteries touch each other in a series configuration to become an equal voltage to the factory original rechargeable pack. i highly advise that you use a test meter to confirm your work AND the original batteries.
slip the plastic circles in between the first contact of the battery compartment and the final contact of the battery compartment. now place your voltage meter probes on each end of the new AA battery terminals that are against the plastic circles. you are testing your new battery pack voltage. in my case it should be near 3.6volts since each individual battery has 1.2volt. when charged. NOW CHECK YOUR FACTORY ORIGINAL BATTERY PACK VOLTAGE. it should also be charged before you test it to compare. make sure they are similar.
Step 3: Step 3 ...
you are nearly done!
now you have some choices. you can join your new battery pack to your factory original battery pack or install a similar mini connector and use it separate from the original.
take your BLACK stripped wire and pull the battery slightly away from the plastic circle insulator and slip the bare wire end between the FLAT END of the battery with the plastic circle insulator at the - NEGATIVE - end of your NEW batteries. NOW YOU MUST STAY ALERT AND CAUTIOUS AS WE PROCEED TO THE RED WIRE!! THEY MUST NOT TOUCH EACH OTHER!
take your RED stripped wire and pull the battery slightly away from the plastic circle insulator and slip the bare wire end between the POINTED TIP END of the battery and the plastic circle insulator at the +POSITIVE+ end of your NEW batteries. STAY ALERT AND CAUTIOUS AS WE PROCEED!! THEY MUST NOT TOUCH EACH OTHER!
now your choices...
Step 4: Step 4 ...
you have choices now.
***unplug the original battery while working on it***
RECHECK THE VOLTAGE OF THE ORIGINAL BATTERY!!!
RECHECK THE VOLTAGE ON THE END OF THE NEW WIRES!!!
IF THEY MATCH..... you can splice the new red to the old red of the factory original battery pack either by soldering or rat tail connections or whatever form of electrical connecting that you are very, Very, VERY good at. then the new black to the old black wire of the factory original battery pack either by soldering or rat tail connections or whatever form of electrical connecting that you are very, Very, VERY good at OR you could find a mini connector which is like the one on the factory original battery and make the proper polarity connections and have an independent new battery pack. !!!!!make the connections and use shrink wrap or electric tape of a thickness equal to or greater than the original insulation on the wiring!!!!!
you might find an old cordless phone or other device that has a mini connector that you can scrounge and re-purpose it ;-)
re-connect the plug from the battery to the radio and test..... enjoy :-)