I have a 12v "alarm" battery from The Shack that I bought about 3 years ago. It weighs about 5 pounds. I use it to operate a small telescope, and haven't used it for about 7 weeks. It was weak, showing 9v on my digital VOM, so I charged it with a 12v 27 AH larger battery last night for maybe 6 hours and got it up to about 11v. After about 2 hours hooked to the telescope doing nothing but showing the small LCD screen, the scope shut down and key lights, and I noticed the voltage at about 8.5.
I took it to an auto store and they used a test meter, and it showed 7v. My neighbor tells me that I should believe the test meter, since it presents a load. I borrowed his trickle battery charger, and will see the VOM reading later. How do I simulate a load to know that I might be able to get 3+ hours out of this battery? The battery should be capable of 7.2 AH. Maybe I just nee