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Battery mod for losi 2.4ghz tx?

Battery mod for losi 2.4ghz tx?

Old 08-22-2009, 09:48 AM
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Default Battery mod for losi 2.4ghz tx?

Has anyone modified one of these to run on 8 aa's? It has a kinda small range with only 4aa's and I was wondering if it was bumped to 8 wouldnt it help? I'm not very good with circuit boards so I have no clue what to look for to be able to tell if I could mod it safely without burning it up.
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Old 08-22-2009, 11:13 AM
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Be careful with this - 4 AAs 4.8v, while 8 would be 9.6v if they were all wired in series. What you need to do is to wire the 4 additional AAs (wired in series) in parallel to the main 4 so the voltage stays the same and you get double the capacity which is what you're looking for.

That wouldn't be hard to do if you have two 4 cell holders - just put the positives and the negatives together from each 4 cell pac.
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Old 08-22-2009, 06:12 PM
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not really.....im looking to increase the voltage to increase the transmitting range if its possible without damaging internal components. These are basically a re-cased spektrum tx, and the spektrum uses 8 aa's. The losi and spektrum tx's and rx's interchange. i was just wondering if the circuit board was the same. these came in the kits with the mini rock crawlers, so they werent really made for range.
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Old 08-23-2009, 09:33 AM
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Misunderstood your ques, my bad.

I don't have an answer, maybe someone has actually done this and found out. I'd want to know if it works before doubling the voltage too, that could just fry something in the tx instead. Good luck
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Old 08-23-2009, 09:40 AM
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yeah, i was hoping some circuit board genius would see the post and know the answer lol. they've become so cheap now(like 20-25 bucks on ebay) im tempted to just try it and see what happens....idk. I'd still like to know if anyone has taken one apart. I could stare at the guts all day and not know if it was capable of handling the extra voltage
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Old 08-23-2009, 11:22 AM
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You will likely fry it. All current Spektrum radios use 4 AA's. DX3S, DX3R, and the RTR 2.4Ghz....

If your having range issues, I would look at the Rx antenna...it works best if it's straight up, even if it is only 3". If it's just laying there to the side, it likely won't work as well.

I have these radios in my Kid's Slash's, and I can drive them as far as I can see down the street, with no issues. After I made the little antenna post for them. It had range issues prior to this...

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Old 08-23-2009, 11:54 AM
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What exactly do you consider "small range"
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Old 08-23-2009, 01:04 PM
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well, i had a rustler with a 5700kv brushless motor on it and i could only go about 50 yards before it started glitching and losing control. I don't think the antenna was straight up though. I wasn't aware that the new spektrums were 4aa's I currently have the setup in an e-revo...but it has a rx box and i currently have the antenna straight up. So maybe it'll be fine now, I'll post when I finally get the last of my parts in. Been waiting 3 weeks for everything
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Old 08-23-2009, 02:58 PM
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I would guess that at 50 yards your issues aren't related to fact that that radio or any other radio only uses 4 cells.
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Old 08-23-2009, 05:27 PM
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I don’t know about the 4 cell Losi/Spektrums, but the older 8 cell DX2/3 have a linear voltage regulator. Meaning that even if the regulator did survive the higher input voltage, the radio circuitry wouldn’t see any more voltage. Given the voltage difference between fresh alkaline and partially ran down ni-mh it seems reasonable to speculate the Losi is regulated too.

Regardless I think it’s risky, modern circuit boards and chips are frequently fairly intolerant of much over voltage. Spektrum has been very clear about not using 2s lipo, and 8 AAs would be higher than that.

Also suggest try working on the antenna, get it up, away from other wiring, avoid kinks.
Even though I don’t have mine sticking up and have given up on finding the range, including both Losi & Spektrum 4 cell jobs.
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Old 08-23-2009, 07:07 PM
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Originally Posted by cyber_06_wolf
well, i had a rustler with a 5700kv brushless motor on it and i could only go about 50 yards before it started glitching and losing control. I don't think the antenna was straight up though. I wasn't aware that the new spektrums were 4aa's I currently have the setup in an e-revo...but it has a rx box and i currently have the antenna straight up. So maybe it'll be fine now, I'll post when I finally get the last of my parts in. Been waiting 3 weeks for everything

Spektrum radios typically don't "glitch". They will shut down and the vehicle just sits there when you have range problems as I have seen.
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Old 08-23-2009, 08:33 PM
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well, it would go so far and then start like spazzing, like throttle no throttle and if i went a little bit further it would just go into nothing and the truck would just roll. Then I could walk closer and it would work. I'll try just having the antenna up and see what that does.
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