Very Inexpensive Battery Maintenance Charger

MEXICOWANDERER wrote:
1.0 ampere output. 13.8 volts regulated charge limit. This unit is good for 100 amp hours worth of batteries. IMO the voltage is a tad high for a high antimony RV battery with temps 60F or higher but an inline 3 amp shottky diode will fix that in a rush (13.5 volts).

http://www.buyincoins.com/item/25902.html

So Mex, are you saying I shouldn't try one of these on my Cotco 6volts since they are 210ah?

I notice that my HF chargers are running 13.68v on the 6volts and 13.99v on my starter battery that I use on my popup (one whole single interior light)

Which brings up another point. How do you measure the voltage on the charger? Do I measure at the battery posts while it's charging up, or do I just clip the alligator clips to the meter leads with no battery in the picture? I notice that if I try to measure at the battery while it's charging the voltage starts out low and slowly climbs over a week or two.