There is a product made by West Mountain Radio that will do exactly what you want. It is called the Super PWRgate PG40S. It has 3 sets of PowerPole connections for power supply, battery, and radio. This unit will do the charging just as you want.
http://www.westmountainradio.com/SuperPWRgate.htm Roger WA1NVC > Am looking for a circuit diagram for a smart battery charger. > Fast-charge-on-low-voltage and slow-charge-on-charged-battery. The values > being programmable. Preferably PIC based. > > The battery is a 12 V sealed Maint free GEL battery 60 AH >
