In article , "Chris" wrote:
Looks like a good project, what should the value of R7 be ?

Sorry I for the missing value
R7 = 10 k ohm
R9 should be 470 ohm
and don't forget a heatsink with more than 5 Kelvin/Watt
Unfortunately I don't have access to the webpages at the moment to replace the
schematic diagram.

Let me warn you to be carful with Chargers for RC modelers.
Most of them are not well designed to charge lead acid batteries.

A good reference for charging characteristics of lead acid batteries can be
found at
http://www.panasonic.com/industrial/...eal/index.html
in the pdf document "VRLA Charge Methods - 508KB".

I use a charger with current limited "two-step constant voltage charge control
method" and temperature coefficient compensation, published some years ago in
Elektor.

Peter Nyffeler
Tel P 01 363 62 42, Tel G 01 632 43 60, Fax G 01 632 10 21