JR 12X & LiPo battery

[jack2k]

Hi all

I was thinking to use a lipo battery on my 12X radio but i'd like to know if someone of you already replaced the original nimh battery with the lipo and how you plugged it !!

thanks,

Jack

[Azlum]

In the beginning of the 12x's manual it explicitly states that you should absolutely NOT use a lipo in any circumstance.

I'm sure people have done it, but is it worth risking your $1500 radio for 50% better battery life?

[enzima78]

I do not understand if that is a problem of voltage...

[Azlum]

Quote from the 12x manual itself:

Q: Can I use a 3-cell LiPo pack in my transmitter?
A: No. All current JR and Spektrum transmitters are designed
to operate using a 9.6-volt transmitter pack. A fully charged
3-cell LiPo pack puts out 12.6 volts. This higher voltage can
overload the power-regulating transistor, causing damage
and or failure, possibly in flight. Many of our customers have
experienced failures using 3-cell LiPo packs and their use in
JR and Spektrum transmitters is highly advised against. The
12X system will operate for over 8 hours using the included
2000mAh NiMH battery.

[jack2k]

Thank u so much Azlum ;) i'll use its pack then as soon as i'll be able to find that radio in stock and at good shipping price abroad ..... anyway on DX7 and JR X9303 2.4 i'm using 3-cell lipo from time and i've never had problems ;)

bye bye

Jack

[enzima78]

Indeed, many radios are designed to 9.6 v but also work well with a 11.1 peak of 12.6 volts.

But I try on my!;)

[MrMel]

everything is possible ;)

I used 2 x 1N4001 (1A 50v) diode in series and one Align/JST-HT balance adapter (6 pin) which I drilled slightly each hole since the JR radio pins are wider (just the plastic).

Pinlayout, looking into the radio, counting from the BOTTOM, is 1-2 = Positive, 3 not used, 4-6 = Negative

as you can see from the pictures, fully loaded lipo shows 11.0v in the radio, might be that its too much drop (low voltage alarm triggers too early), but that I will check when I have run it for a while, then its just to try other diodes, but I think im good.


Also, as you can see, there is lots of space, if you can find the perfect sized pack you could probably fit around 3000-3500mah in there.

Obs: Remember to put a CHARGE lead on the battery, you CANNOT charge through the diodes.

Diodes in this picture wrapped in the heatshrink.
http://heli.dacsa.net/12x/cimg2863.jpg

Some RX Foam on a double-sided tape so the battery wont fly around :)
http://heli.dacsa.net/12x/cimg2864.jpg

As you can see, there is much room if you can find a perfectly sized lipo.
http://heli.dacsa.net/12x/cimg2865.jpg

http://heli.dacsa.net/12x/cimg2867.jpg

http://heli.dacsa.net/12x/cimg2868.jpg

[John Cook]

thanks for the guide and pin-out. I put my lipo from my X9303 into my 12x today :). I was unhappy with the performance of the stock NiMh in the 12x as it dropped in voltage too much/fast for my comfort. I used a 7 pin JST-XH balance connector, trimming off one of the tabs to make it a 6 pin connector. Put in one of the diodes instead of 2, and I get about 11.3v on the LCD readout when my pack is charged about 90% and I think I'll leave it there :).

[TmMugen]

Any idea what is the voltage like until the alarm sounds?

[KingKow]

Sounds like a good plan. Any chance that you would have some photos?

Thanks a lot.
thanks for the guide and pin-out. I put my lipo from my X9303 into my 12x today :). I was unhappy with the performance of the stock NiMh in the 12x as it dropped in voltage too much/fast for my comfort. I used a 7 pin JST-XH balance connector, trimming off one of the tabs to make it a 6 pin connector. Put in one of the diodes instead of 2, and I get about 11.3v on the LCD readout when my pack is charged about 90% and I think I'll leave it there :).

[John Cook]

Sounds like a good plan. Any chance that you would have some photos?

Thanks a lot.
I just used the ones in this thread myself

[Danal Estes]

Um, why LiPo?

Usually it is:

1) Low Self Discharge (always ready to fly)
2) Capacity

but the risk list is long: Voids your warranty, cause a fire if mis-charged (not as big a risk with the 12x, no charge jack on TX), some risk that higher voltage may be bad for TX in long run, is low voltage calibrated correctly, have to use a LiPo charger... and on and on.

Have you considered eneloops? They are a high-capacity, low self discharge NiMh. Availabile in AA size, so you could "reload" the stock pack.

They have all the advantages of LiPo, and none of the risks.


:)

[MrMel]

AFAIK the eneloops are too big to fit.

For me its above points but also the weight, to get the radio to balance better, and that you cant get with something else.
Ive been (and a few friends which I built packs for) running the 12X since it was released with this type of Lipo packs with "stepdown".

Edit, forgot, also, keep voltage under freezing temps, which stock battery had trouble with, no issue to fly in -10C with lipo.

[John Cook]

AFAIK the eneloops are too big to fit.

For me its above points but also the weight, to get the radio to balance better, and that you cant get with something else.
Ive been (and a few friends which I built packs for) running the 12X since it was released with this type of Lipo packs with "stepdown".

Edit, forgot, also, keep voltage under freezing temps, which stock battery had trouble with, no issue to fly in -10C with lipo.
OUCH
how about your poor fingers in -10C eheh

[Danal Estes]

AFAIK the eneloops are too big to fit..

I haven't tried it physically in a 12x carrier, but the datasheet for the eneloop cells says they are the same dimensions as the ANSI spec for a AA cell.

Unless the cells that ship from the factory are some truly oddball thing, the eneloops should be EXACTLY the same size as the factory cells. Should fit the carrier just fine.

I was unable to find a datasheet that says how they perform in the cold!! Brrr!!! :)

[TheSteve]

The stock nimh AA cells that Jr uses are slightly shorter then an Eneloop. You can still use Eneloops in the 12x battery holder though as long as you assemble them very carefully. I spot welded up a pack and have been using them in my 12x since the radio was released. I bought a bunch of Eneloops onsale - 8 for 14 dollars, pretty tough to argue at that price.
Being they have no self discharge I prefer them to LiPo - to me the only advantage LiPo would still offer is with respect to balance. I really like I can charge the battery in the radio and never worry about any LiPo related issues.

[MrMel]

I haven't tried it physically in a 12x carrier, but the datasheet for the eneloop cells says they are the same dimensions as the ANSI spec for a AA cell.Ive been told over at RR that if you buy a 8-cell eneloop brick pack it WONT fit, period (3mm difference), and as steve says its bigger and only way is probably to build your own pack, carefully.

[Danal Estes]

Ive been told over at RR that if you buy a 8-cell eneloop brick pack it WONT fit, period (3mm difference), and as steve says its bigger and only way is probably to build your own pack, carefully.

I have no trouble believing a pre-assembled brick pack won't fit.

I was making too many assumptions and therefore was not clear: I was assuming anyone interested in eneloops would buy bare cells and assemble them into the existing 12x carrier, to take advantage of the existing radio connector and charge connector.

Regarding the spec, I should have been more precise in my phrasing. The Eneloops are the same size as the ANSI standard for AA NiMh cells (which are not the same as ANSI AA cells). The spec does allow a little +/- tolerance... Therefore, eneloops should fit in the 12x carrier, with some possibility of being a bit looser/tighter than the stock cells.

Combine the two assumptions I made in my phrasing and I see where I was not very clear. Sorry.

And all phrasing aside, Steve proved that if you assemble the cells into the carrier yourself, they fit. If somewhat tightly. :hug:

[MrMel]

Thing is that to use the original carrier, you have to make a brick, you cannot put in loose cells, and hence the problem, you have to make the pack perfectly for it to fit, using the correct tools and be lucky...

[Racer38]

Why not purchase a premade TX Lipo Pack, I know outrage makes them and there are several others as well.

[MrMel]

12X WILL burn if you run direct lipo in them, not like DX7, 9303 where they survive

[John Cook]

Why not purchase a premade TX Lipo Pack, I know outrage makes them and there are several others as well.
they come with jst connectors not the modified connector in the 12x. I don't think this post was so much "wow I put a lipo in a Tx, thread" moreso showing the pin out etc...
I put the "pre-made" Zippy lipo I had in my X9303 into my 12x after following the pin out guide :). With one step down though.

[John Cook]

12X WILL burn if you run direct lipo in them, not like DX7, 9303 where they survive
why is that MrMel? I mean, I'm not trying to argue with you, I just want to know. I would almost assume(yes that bad word lol) that the PR put out by JR is FUD so people don't put lipos in and buy their expensive "upgrade" batteries, whenever they are out. I'm just not sure what would make a 12x more sensitive than the X9303 or DX7, as the voltage regulator would have to be of the same quality or better I would guess.

John

[MrMel]

why is that MrMel? I mean, I'm not trying to argue with you, I just want to know. I would almost assume(yes that bad word lol) that the PR put out by JR is FUD so people don't put lipos in and buy their expensive "upgrade" batteries, whenever they are out. I'm just not sure what would make a 12x more sensitive than the X9303 or DX7, as the voltage regulator would have to be of the same quality or better I would guess.

They went out with a specfic disclaimer that its transmitter board is more senstive then the DX7/9303, where as "unofficially" lipo that work in the DX7 it will burn up the 12x.
Cant find that post now though, I but I know I read it, gonna search a little more and see if I can dig it up again.

[MrMel]

(then again, Ive seen one 12x radio with direct lipo, so it might work for some question if you want to risk it)