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Analyzing Car Charger for HAM Radio Battery pack

Well, I've been searching the interwebs for the last couple hours, attempting to find an analyzing charger I can modify to use with my Baofeng UV-5R battery packs. I have a couple factory charger I can scavenge the connection and docking system from, I just need a charger capable of running off of vehicle 12v and charging a nominal 7.4v battery pack. I, so far, have had no luck. I have looked at some of the available hobby chargers, but most of the ones that come close can only charge one pack at a time. I would like to at least be able to charge two packs at once, controlled individually, and preferably three.

I am posting this in the projects forum because I plan to look into making one if one is not commercially available.

If no one is aware of such a beast, I would like to try my hand at making one. I am fairly familiar with Li-Ion packs, however I can not say the same for the circuitry used by the actual chargers.

What I have managed to find is this datasheet, which seems to be the type of charging circuit I want, however I still want a discharge option and a display...http://www.ti.com/lit/ds/symlink/lm3420.pdf and I also am wholly unfamiliar with SMD components, other than knowing they are SMD when I see them lol. Is there a through-hole option that is capable of similar things?

So my situation boils down to this, if someone can point me to an analyzing charger that I can modify for the docking station of my radio/battery packs I would be eternally grateful. If not, then if someone could point me in the direction of a through-hole component that is similar in capabilities to the LM3420, I again would be eternally grateful.

As an aside, the current factory charger has a 12v plug that I acquired. Apparently the input for the factory base can safely use from 10-12v, but as we know a vehicle normally puts out more than this. The 12v adapter for the factory base has no voltage regulation, so when voltage peaks above the safe 12v for the base, the base shuts off. I would like to make a quick fix for this (otherwise charging takes a ridiculous amount of time), so that I can go ahead and charge my batteries on the fly. Am I correct in thinking a simple resistor will work as a temporary fix until I can find and/or build an analyzing charger?

Thanks ahead for all time and effort invested!!
 
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Well crud, my google-fu must be weak tonight. Much appreciated!!

That does what I need, but dad-blame I was hoping I could find something smaller and honestly less expensive. Hmmm.
 
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