Honda: 89 honda civic, 89 honda civic, alternater

Question
my battery light is on but when the car is at high rpm the light turns off and recently my battery has gotten real low but I just bought the battery last october, now even if the car is on and running I can't turn on anything electerical with out the car turning off. I just want to know if it is my alternator or my battery? And if it is my alternater is it difficult to take off and replace? Thank you

Answer
Sound like the alternator,it is sort of difficult to remove the alternator but if you locate a shop that will sell you the brushes you can replace them without taking ist off.I've done it several times on my 90 civic a ramaned alt is about 170 the brushes are only about 17.