Me again.
Thanks for the info. I just decided to run it down to see how long it would
go. Like I said before, after fresh charge, and the battery showing 14v,
after aplying the slightest load, the voltage started dropping... it dropped
down to 12.6 in no time, but.... its been staying there. I've had the radio
on for a couple hours, and its not moved from 12.6v. I even keyed a bunch,
and that draws about an amp. Seems its holding steady at that voltage under
load.
Thanks again guys, your always more than helpful.
Jim, AB9LM
"J Shrum" wrote in message
...
Hey guys... I've spent lots of time looking over google archives for the
answer to this, and God knows this has been covered many times, but I've
not quite found my answer.
I have the following QRP power supply/charger
http://www.mfjenterprises.com/produc...rodid=MFJ-4114 .
Basically it comes standard to charge a 12 nicads, but I took out the
nicad holders and put in a 12v 5AH gel cell. I modified it to charge
directly from the 13.8v power supply instead of the 18v nicad charger
circuit. I charged the battery to about 13.8v (w/ no load) by floating. If
I measure the battery while having my radio on receive, which only draws
maybe 80mA's or so, I see the battery dropping by .10's of a V in no time.
The battery is brand new.
I've noticed that the battery only draws about 30mA's while charging at
any voltage. I even added a switch so I can switch extra diodes between
the regulator ground so I can charge it at 14.X volts.
So my question... If it measures 13.8-14v after charging, it should be
fully charged, right? Is there something going on since it is only drawing
10's of milliamps while charging? I've read that they charge at several
hundred milli's. I'd like to use my QRP rig remotely, and at the rate its
dropping, I just don't think it will serve the purpose.
Thanks for all the help.
Jim, AB9LM