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Jedi charger modifications

Posted: Mon Dec 15, 2003 11:23 am
by motor59
I know that there were a few threads in the past discussing mods to various Jedi chargers, to allow them to float charge the battery without cooking it.

Anybody ever get anywhere with this?

I just had to replace a battery with a 147 datecode, because it won't last more than 2 hours in mostly RX-mode, once it come out of the PAC-RT charger.

My application dictates that 99% of the time the radio sits in the truck, but those times when I need it, I need it right then. I tried establishing a routine of charging/removing the radio, but that didn't seem to work out too well.

I need a charger that will keep my battery topped off, without cooking it.

Suggestions?

Posted: Mon Dec 15, 2003 2:46 pm
by RKG
There isn't such a device.

Best bet is a vehicle charger and two batteries. Batt No. 1 is on the radio, which is not in the charger. Batt No. 2 is in the glove box. When the bells sound, go to the job, exit with Batt No. 1 on the radio and put Batt No. 2 in the charger. Swap batteries as needed.

In order to have a true float charger -- a charger that neither transfers any current to a charged battery (other than to offset shelf discharge) nor allows the battery to carry the load of any attached devices -- you have to have a battery whose float point is known and stable. This works for larger flooded cells, or more accurately, for large banks consisting of multiple large flooded cells. It does not work for small batteries with NiCad or NiMH chemistry.

That said, it may be possible for you to recover some of the lost capacity of your batteries. Put one on the radio and leave it on, preferably in scan. Leave it on after the beep starts, until the display dies entirely. Then put the battery in a rapid charger, until the light goes green plus three hours. Repeat the cycle at least twice.

Posted: Mon Dec 15, 2003 9:19 pm
by Macon Sparks
Do you have access to a conditioner?

A triple cycle is the best thing for batteries that have become lazy.

Chargers

Posted: Tue Dec 16, 2003 6:07 am
by 1 Adam 12
What you are looking for is the AdvanceTec conditoning charger... also sold by Motorola as the their conditioning charger... The part number under Motorola is WPLN4090AR which includes the charger, adapter plate and cigarette lighter cord. These are excellent chargers that will not cook a battery. If you go to AdvanceTecs website you can look at the process and theory.. All I can say is they work... I have use them since they came out in both mobile, marine and office applications. One word of caution... no Lithium ion batteries, only Nicads and NMH batterries.
http://www.advancetec.com

Posted: Sun Jan 11, 2004 10:33 pm
by thehead7
I've got the Jedi conditioner/chargers. I'd be more than happy to condition batts... All it would cost is return shipping if they are recoverable...

I think it says NiCD only, though... Might work with NiMH, but I wouldn't want to try Li-ion...

PM if you want my help.

-Head

Posted: Mon Jan 12, 2004 1:58 am
by Will
On the Jedi and GP3xx series rapid/dualrate chargers there is a simple change to reduce the so-called "trickle" or more accuratly the "Complete" to a current that will not kill the battery. Usally 10 to 15 ma for the 1500 ma battery.
Only problem is that there are up to three different versions of the circuit boards in the chargers. Basically there is a resistor(s) from the input voltage at the power jack going to the battery + contact that determines the rate of charge in the "Complete" or trickle mode.

The NTN1171A has three 62 ohm resistors in series, = 186 ohms. That would be about 30 to 40 ma. depending on the accual voltage into the charger. This is too much to have going into a already charged battery, it will eventually "fry" the battery.

Posted: Thu Mar 18, 2004 5:54 pm
by Motradio
Will -

I got a couple of NiMH moto bats, and I was unsure if 'safe' to charge on the NTN1171A's. I gave one a try until it seemed to get hotter then I liked when I checked it (2 hrs), I hope it didn't do any harm. The question is if is it just the trickle current as dictated by the 3 resistors that need to be changed to make this safe to use with the Moto NiMh batts, or will it not work at all, the resistors are an easy fix to reduce the current if that is all it is.

I also have the 'shoe' style that says only NiCad ONLY on the several I have, I can't remember if you or someone else had mentioned that they charge them up just fine. Probably don't want to try one in them either, but not sure.

Thanks

Sandy

Posted: Fri Mar 19, 2004 1:08 am
by Will
I have used NiMh bats in the Jedi desk top charger witout any problems. I did write the mod for the chargers under a post "GP300" a couple of days ago. Basically changing the three 62 ohm resistors to total about 330 ohms works well alowing only 20 ma current in the COMPLETE mode, that seems to make the battery cool way down right away and is a safe current to leave the battery in the charger for a day or so.

Now there is another more serious problem in the charger design... if the AC power goes away or "browns out', the charger comes back on in FULL CHARGE on your allready charged battery. I have not found a simple way to make the charger come back on in the COMPLETE mode if there is a battery in it. I have made some mods to the P200/HT600/MT1000 and P100/HT50 chargers to do that.

I have not had the chance to look at the PAC-RT charger to see if it can be made a lot more battery safe. Not that I would not like to look at one... anyone got a "roadmap" for one, or one to look at?????????

Posted: Fri Mar 19, 2004 10:08 am
by Motradio
Thanks Will -

I'll mod up one of the chargers and give it a shot. Looks pretty easy to get the 3 SMD (1206 size as I recall, but I better check again) resistors out and replace with 110 ohm'er. Looks like I need to gather a mouser order up. I almost never leave the batts in the chargers more then over night, just a fire paranoia I guess, but better safe the sorry with the fix.

The power fail problem is not much of a concern for me, more bumping the chargers and starting the cycle over which I would expect the charger is not to sofisticated and will have the same problem.

Thanks

Sandy

Posted: Sat Mar 20, 2004 3:50 pm
by Ed
Somewhere on the web: "U can use the Saber charger in case of emergency, to recycle the Jedi batteries" Did not try it/did not believe it, but it sure has the same pins. The Saber charger has more intelligence inside. So there's a core of truth???? Who has tested this one?


Ed

JEDI Charger help

Posted: Fri May 27, 2005 1:31 am
by kato56
Hi Will,
I've been searching the archives on JEDI chargers for my 2700 MAH NiMH JEDI batteries and saw your post. I bought a NTN7209A charger on eBay thinking I could charge my NiMH batts, but it must be a NiCad only since after placing it in the charger, it reverts to green (complete) in about 5 minutes.......
Is there a mod for the NTN7209A to charge NiMH batts???????

BTW, I also have a NTN1171A charger, but isn't that a NiCAD only charger also????

Thanks, Duane
Will wrote:I have used NiMh bats in the Jedi desk top charger witout any problems. I did write the mod for the chargers under a post "GP300" a couple of days ago. Basically changing the three 62 ohm resistors to total about 330 ohms works well alowing only 20 ma current in the COMPLETE mode, that seems to make the battery cool way down right away and is a safe current to leave the battery in the charger for a day or so.

Now there is another more serious problem in the charger design... if the AC power goes away or "browns out', the charger comes back on in FULL CHARGE on your allready charged battery. I have not found a simple way to make the charger come back on in the COMPLETE mode if there is a battery in it. I have made some mods to the P200/HT600/MT1000 and P100/HT50 chargers to do that.

I have not had the chance to look at the PAC-RT charger to see if it can be made a lot more battery safe. Not that I would not like to look at one... anyone got a "roadmap" for one, or one to look at?????????

Posted: Tue May 31, 2005 7:40 pm
by RadioSouth
NTN7209A aka NTN1168A when supplied with a US cord is compatible with NiCad and NiMh batteries. Is this 2700 MAh battery an aftermarket ?

Posted: Tue May 31, 2005 8:41 pm
by mancow
Ed wrote:Somewhere on the web: "U can use the Saber charger in case of emergency, to recycle the Jedi batteries" Did not try it/did not believe it, but it sure has the same pins. The Saber charger has more intelligence inside. So there's a core of truth???? Who has tested this one?


Ed

Yep, did it for quite a while before I had a jedi charger. They have the same pin spacing and battery voltage rating. It worked just fine. I can't condone it, don't know the actually differences if any but it worked.
It was a :o keeping the battery in the right spot.


mancow