Charging problems

[oldhotrod]

BATT reads 12 volts,alt off car reads 13 volts put alt back on car scan master shows 10-11 volts, batt will run down ??? I have a volt booster,could it be the problem? can you help?
Jerry

 

[TurboDave]

If it's a RA volt booster, most likely it has eaten your alternator for lunch. As it did to 3 of mine before I wised up.