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Direct connection from Lithium Ion 7.2V to receiver & servos

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Old 03-11-2008, 09:51 PM
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Default Direct connection from Lithium Ion 7.2V to receiver & servos

Yes, I did it lastnight. Test it for 10 minutes.

Long story short : I bought two SONY rechargeable Lithium Ion 3.6V - 1200MAH, put them in series, charge it, and plug it directly into Futaba R203HF (HRS) and Hitec 5995TG servos. It was awesome. My buggy's steering and brake swings the horn like crazy super fast . It's 20% over voltage than spec ( 6V).

I'm gonna test it for 1hr racing oneday. ( IF anybody has any electrical experience about over voltage, and you know what I'm doing is wrong, please help me now... so I can stop ).



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Old 03-12-2008, 02:12 AM
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It will work fine but sooner or later the regulater in the reciever or servo will pop.
I ran mine for a couple of months before i melted my Fuatab and KO servos.
Get a 5 amp lipo regulater and you will be safer and still benefit from the better performance of the servos.
A 1200mah pack should easilly give you 45 - 60mins run time.
my 1400 li ion bat gave me 1hr 15 mins before it hit the voltage cut off on the regulater and that was in my 1.8 buggy.
I am using a 1800 7.4v pack with a VRX lipo regulater.

Better safe than sorry
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Old 03-12-2008, 04:02 AM
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for lipo batteries you should use a voltage regulator exept for spektrum receivers(they have oem installed regulator inside) the spektrum equipment(all) not need regulator for lipo but other brands need an external regulator.Hope the servos do not burn. I have a friend who have that experience.
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Old 03-12-2008, 05:51 AM
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Originally Posted by JRGTR
for lipo batteries you should use a voltage regulator exept for spektrum receivers(they have oem installed regulator inside) the spektrum equipment(all) not need regulator for lipo but other brands need an external regulator.Hope the servos do not burn. I have a friend who have that experience.
that'll be a great news! but where/how do you know that?
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Old 03-12-2008, 05:55 AM
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About the Spektrum receiver, where can I read about its regulator, do you know ?
Does it regulate the connection for the servos too ?
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Old 03-12-2008, 07:41 AM
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Never heard about Spektrum having a regulator????..............Can someone in the know verify this?????????????????
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Old 03-12-2008, 09:57 AM
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well, I was running last year with a spektrum dx2 and lipo batteries and don't have problems and when I purchase the lipo battery the sales person on the hobbie shop ask me about the equipment that I was using and I told him that I use spektum and he do not sold me the regulator because he explain me that spektrum tx rx including the modules for other tx donn't need it. the other brands need it, but in other hand I run now with a M11 with the 2.4 air tronics and now I need to use regulator. second my best friend use futaba 2.4 fast with lipo he did't install the regulator and surprise the first race he burn the servos and damage the receiver.
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Old 03-12-2008, 10:15 PM
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I think spektrum has wide operating voltage, from 4.8V to 9.6V. Not sure about voltage regulator built in. Please read again spektrum manual for assurance. ( I don't have spektrum receiver ).
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Old 03-12-2008, 10:20 PM
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Originally Posted by JRGTR
second my best friend use futaba 2.4 fast with lipo he did't install the regulator and surprise the first race he burn the servos and damage the receiver.
So I better buy a voltage regulator instead of risking everything ( race position, 1 receiver, and 2 servos ).
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Old 03-13-2008, 06:59 AM
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Originally Posted by asw7576
So I better buy a voltage regulator instead of risking everything ( race position, 1 receiver, and 2 servos ).
yeah, one of my team mates uses the M11 with spektrum pro and never have issues with the lipo battery I never have lipo issues with spektrum now i need a regulator or buy a spektum pro for my M11 to use again is a big diffrence with lipo, less weight and moore servo response.here on P.R. are difficult to find regulators
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Old 03-13-2008, 11:26 AM
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Default Low Voltage

LIPO batteries should not be over discharged. If you do not have a low voltage cut off somewhere in the battery circuit you may over discharge your batteries. They will not recharge if over charged and I have heard one person say that they had a pack catch fire when trying to charge a pack that had been over discharged.

I use the NOVAK 5460 with my lipo packs.
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Old 03-13-2008, 11:43 AM
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Originally Posted by Taylorm
Never heard about Spektrum having a regulator????..............Can someone in the know verify this?????????????????
Yes, it has but not for the servo's...

It is not wise to do this, full charges LoPo's will have about 7.5 to 8 volt and that is way to much for the servo's under heavy load.

I know there is a brand servo which can handle up to 12 volts....
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Old 03-13-2008, 05:46 PM
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yes Roleof is right.
The regulator will protect a spectrum reciever because it is upstream in the reciever but the servos use +-power in pass through on the board and only the signal comes from the reciever. Don't use a regulator and you will smoke servo's. Been there done that! You will cook them on straight 2 cell lipo without a regulator maybe not immediatly but within a month it will happen.

I cooked 3 KO's this way and it was on a road trip race. A weekend trip across the U.S. became a total bust
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Old 03-13-2008, 05:50 PM
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I use the thunder tiger regulators. their cheap, small and solid and they have a reliable switch.
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Old 03-13-2008, 06:05 PM
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Regulator without a switch. If you want a switch, change the part number to 9608

http://www.losi.com/Products/Feature...rodId=LOSB9609
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