<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META content="text/html; charset=iso-8859-1" http-equiv=Content-Type>
<META name=GENERATOR content="MSHTML 8.00.6001.18854">
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV><FONT size=2 face=Arial>Bob,</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>I would only trickle charge the batteries as a
routine (100 mA or less) once they are brought to full charge. Much better is to
charge such batteries as needed. These do not appear to be SLA's, so there will
be venting. What gets vented is Hydrogen gas (flammable, can have an explosive
concentration issue and over time, years, will belch a very tiny amount of
dilute sulfuric acid). Hydrogen flame is invisible unless it is burning
something else. I would keep such a setup <STRONG>out in a well ventillated
garage</STRONG> and consider the fact that car batteries can explode. Hydrogen
builds up, there is an arc inside the battery or a source of ignition external
to the battery. This will splatter the sulfuric acid over an area and on people
if you happen to be nearby. Then there is the shrapnel from the battery
case!</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>I had a battery blow up in a 64 Chevy. It was a
Sears battery with a year or so to go on the warranty. I thought I was the
victim of a car bomb (radical politics days-thought the Birchers got me) and my
ears were ringing for hours afterwards. The only idenfifiable part of the
battery case was th botton inch or so and some of the lead plates. It was
terrible decontaminating everything under the hood!</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>The inverter will be expensive and might generate
noise on HF.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>All my stuff is 12 V, including a CFL that lights
up the shack.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>The 130 A/hr telcom batteries at the hamfest are a
better idea.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>You could build a Schottky diode device to trickle
charge and automatically switch over to battery on power failure.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>George</FONT></DIV>
<BLOCKQUOTE
style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=N1UJS@toast.net href="mailto:N1UJS@toast.net">Bob</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=450@lists.vhfwiki.com
href="mailto:450@lists.vhfwiki.com">144.450 Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Sunday, December 13, 2009 11:44
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [450] battery backup
project</DIV>
<DIV><BR></DIV>
<DIV><FONT size=2 face=Arial>Successfully revived two Orbital batteries for
backup purposes. </FONT></DIV>
<DIV> </DIV>
<DIV>
<DIV><FONT size=2 face=Arial>Battery specs. are here:</FONT></DIV>
<DIV><FONT size=2 face=Arial><A
href="http://www.remybattery.com/Products/Exide-Orbital-ORB78DT-84-Starting-Battery__ORB78DT-84.aspx">http://www.remybattery.com/Products/Exide-Orbital-ORB78DT-84-Starting-Battery__ORB78DT-84.aspx</A></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV></DIV>
<DIV><FONT size=2 face=Arial>The plan is to tie them together as a backup
supply for the entire shack in conjunction with an inverter (anyone got one
cheap to trade or sell?). </FONT></DIV>
<DIV><FONT size=2 face=Arial>Total cash outlay so far, $18.00 ("core
value" for the two batteries). They were new, but on the shelf at
work since '05. </FONT></DIV>
<DIV><FONT size=2 face=Arial>They seem to be good as new after charging with
my Samlex APS 1215 (shown below, 15A cont., 20A surge) which will be devoted
to keeping them charged.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial> <IMG style="WIDTH: 200px; HEIGHT: 105px"
border=0 hspace=0 alt="" align=baseline
src="cid:1262B88DBDA0481792A4EE463884D78D@georgen1yae"></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<P>
<HR>
<P></P>_______________________________________________<BR>450 mailing
list<BR>450@lists.vhfwiki.com<BR>http://lists.vhfwiki.com/cgi-bin/mailman/listinfo/450<BR></BLOCKQUOTE></BODY></HTML>