Check the alternator to see if it is putting out enough voltage/current to charge the battery. Of course, check the battery cable clamps and other connection to make sure that they are clean and bright.
I have learned that when i get new batteries for my hobby cars you want to fully charge the battery to the recommended hrs, you want to charge the battery fully because it will improve how long your battery will last on one charge and how long the battery's life will be.
You cannot change the amps in an existing battery. If you want to increase the CCA you will have to purchase a new battery with a higher rating.
if a battery won't charge then it is proboly broken and you might have to replace it
Yes, your can charge the battery with the radio on. But why would you want to do this? It will just take longer to charge with something drawing current from the battery.
buy a new battery.
30 year old battery?? I have never heard of a battery lasting this long. This has to be a record of some sort. I would contact the battery manufacture as they may want this battery and give you a new one for it. Anyway if the battery will not hold a charge it has a dead cell and needs to be replaced.
A new battery doesn't mean a good battery. The new battery may be defective. Return it and get a new new one.
New batteries almost always come fully charged. If it was not then charge it with a battery charger and do not use your vehicle alternator to charge a dead battery. You may do harm to the alternator which is not built to charge a dead battery but is instead built to keep a good battery fully charged.
As long as both batteries are the same voltage, you can jump start with the battery. If you want to charge the battery then use a battery charger.
Your battery will lose charge faster.
If the battery is defective get a new battery. If you just left something on and ran it down, charge the battery and keep going.
Dead Battery. Are you sure your battery can maintain or hold a charge?