KCØPET Pages
Portable AA4PB Battery Charger
I have built several of the AA4PB battery chargers for Sealed Lead Acid batteries and have found this to be an excellent design. None of my chargers are very portable, so I decided to build a portable version of this charger for traveling. I also had almost all the parts in my junk box, so I only had to order a few of the parts. I used Altiods tins for the enclosure, so the total cost was just a few dollars. I am also using a 16 volt AC power cube that I had around.
A single tin was not big enough, so I mounted 2 tins back-to-back:
One compartment is the "hot" side or the power side with the voltage regulator, current limiting resistor, heat sink, bridge rectifier, etc. Definitely "ugly" construction:
The other compartment is the "control" side. As you can see, this is built manhattan style. Note the SMT IC. This is an LM358; the only one I had on hand was an SMT version, so I made an adapter board for it. That prompted me to make a similar board for the LM555 even though it is a through hole version. I recently disovered that there is an article in "Homebrewer #5" by N5IB on making SMT manhattan pads which would have been easier than my "dremel wheel" method (unfortunately Homebrewer is out of print).
For a parts list, see my Modified version of the AA4PB Charger. I eliminated the PC board, enclosure, one of the power supply filter caps and made some other substitutions for this version.
For the original article see "An Automatic Sealed Lead Acid Battery Charger" in the May 2001 QST (must be an ARRL member).
