Thanks, Bob. The start battery is close by, and it's charging current is typically low (5 amps) since it does not get discharged much. I really just want to keep it at about 13.8 v or so, to put back the charge lost by starting, and the amount used by the electric fuel pump and electronic ignition. What P channel MOSFET did you get? That's exactly what I want. Thanks --=20 Larry Bradley =20 Orleans (Ottawa) Canada=20 On Fri, 2014-02-07 at 10:50 -0700, Bob Axtell wrote: >=20 > We use a heavy P-MOSFET to deliver the charge to the battery. EBay=20 > sellers from China have the best prices for some reason, at 1/3 the=20 > price of Digikey & Mouser. I am distressed at ordering from China but=20 > being poor, I am forced to seek the lowest price. >=20 > Bob A >=20 > --=20 >=20 > The only place success comes before work is in the dictionary. >=20 > VINCE LOMBARDI >=20 --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .