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<DIV>Troy,</DIV>
<DIV> </DIV>
<DIV>Well, that is clear like water. Thanks for the feedback. I was checking alternates since I need to replace the TX batteries for next season. I will keep using the NiMh as you recommended. </DIV>
<DIV> </DIV>
<DIV class=signature id=signature>--<BR>Vicente "Vince" Bortone</DIV>
<DIV> </DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">-------------- Original message -------------- <BR>From: "Troy Newman" <troy@troynewman.net> <BR><BR>> Vince, <BR>> <BR>> While its not recommended there are several people that have done it. I <BR>> will say that because you will hear of XXX people that have done it with <BR>> no problems. <BR>> <BR>> JR does NOT recommend it and here is why: The output of the system is <BR>> driven by a specific design voltage. In the 72mhz stuff the output <BR>> transistor would get hot if the system was run at the higher voltage. A <BR>> 3S lipo pack comes off the charger at about 12.4-12.6V....A fully <BR>> charged stock battery pack comes off the charger at about 11.5 to 12V. <BR>> Here is what I think you should look at. The Lipo pack will maintain is <BR>> "over voltage" condition for a long time. It will stay above 11.5V most <BR>> of the time you sp
end fl
ying it. Where as the Nimh or Nicd packs will <BR>> fall off to about a 10.5V range and slowly come down from there. The <BR>> high voltage condition is only for a few minutes maybe the first flight. <BR>> The lipo high Voltage condition is a long time maybe 5-8 flights. <BR>> <BR>> The issue with the 72mhz equipment was the output transistor would get <BR>> hot and start to weaken causing loss of range and possible a failure. <BR>> This is the same problem as running your TX on 72mhz and leaving it on <BR>> for long periods of time with the antenna down. The module gets hot. <BR>> This is un-needed wear and tear on the output transistor. Continued <BR>> abuse like this will weaken the output transistor...In the lipo you are <BR>> running it in a "high" volt condition for a longer period of time every <BR>> time you charge the system up. So yes it will work on day #1 and Day <BR>> #2....but What happens on Day #50 or 9 months down the ro
ad. 1
yr later? <BR>> Its not a good idea as it will weaken the system and it could cost you a <BR>> model. <BR>> <BR>> Fast forward to the DSM technology. Again we have a similar situation. <BR>> The output of the system was designed to be run at a given voltage. That <BR>> voltage is the 8cell (nicd or Nimh) packs. Not the extra 1V of head <BR>> voltage carried in the 3S lipo packs. I'm not in on the design of the <BR>> DSM output and can't tell you if it has a similar issue to the one in <BR>> the 72mhz. However in the 12X manual it states clearly.... <BR>> <BR>> "Q: Can I use a 3-cell LiPo pack in my transmitter? <BR>> <BR>> A: No. All current JR and Spektrum transmitters are designed to operate <BR>> using a 9.6-volt transmitter pack. A fully charged 3-cell LiPo pack puts <BR>> out 12.6 volts. This higher voltage can overload the power-regulating <BR>> transistor, causing damage and or failure, possibly in flight. Many of <BR>>
; our
customers have experienced failures using 3-cell LiPo packs and <BR>> their use in JR and Spektrum transmitters is highly advised against. The <BR>> 12X system will operate for over 8 hours using the included 2000mAh NiMH <BR>> battery." <BR>> <BR>> <BR>> <BR>> This being the case the 12X is the latest system from JR. SO if it is <BR>> not Lipo capable the others are not either. Will it work? Yes, are you <BR>> taking a chance and risking your model YES. <BR>> <BR>> I don't understand the rave with the lipo TX packs. The 12X pack that <BR>> comes standard is a 2000mah pack. A replacement pack would be a <BR>> 2000-2100mah pack also... So you are not going to get more flight time <BR>> per charge. The only thing is the lipo will not self discharge as fast <BR>> as the Nimh. However I find the Nimh packs last for a very long <BR>> time....Still flyable (10.5V) after sitting for a month untouched. One <BR>> note I usually charge
my TX
packs with the wall C/10 charger overnight. <BR>> I sometimes will use a Sirius charger on them or a peak detection <BR>> charger for a quick field boost if its getting low. However This is a <BR>> rare thing. 90% of my charging is with the slow c/10 charge rate. At <BR>> this the Nimh packs provide extremely good service life and hold their <BR>> charge well. A guy that is always fast charging his nimh batts will have <BR>> trouble with the Nimh technology. It doesn't do as well with this type <BR>> of use. <BR>> <BR>> <BR>> By the way JR makes a 2500mah nimh that I have placed in my 9303 and <BR>> also have installed in an old 10X battery case. It works great as well. <BR>> <BR>> <BR>> <BR>> Hope this helps you. <BR>> <BR>> Troy Newman <BR>> Team JR <BR>> <BR>> <BR>> <BR>> ________________________________ <BR>> <BR>> From: nsrca-discussion-bounces@lists.nsrca.org <BR>> [mailto:nsrca-discussion-bounc
es@lis
ts.nsrca.org] On Behalf Of <BR>> vicenterc@comcast.net <BR>> Sent: Tuesday, September 23, 2008 3:35 AM <BR>> To: General pattern discussion; General pattern discussion <BR>> Subject: Re: [NSRCA-discussion] JR 10X conversion to LiPo <BR>> <BR>> <BR>> Jerry, <BR>> <BR>> Are you using regulator? It looks like JR does not like the high <BR>> voltage. Probably, I am going to try to call or e-mail JR to ask. I <BR>> wonder if there is a difference between the 2.4 modules and the old <BR>> modules in regard taking higher voltage. New TX are designed to work <BR>> with LiPo. Just wondering. <BR>> <BR>> JR sponsored pilits. Can you find out? <BR>> <BR>> Thanks for all responding. <BR>> <BR>> -- <BR>> Vicente "Vince" Bortone <BR>> <BR>> <BR>> -------------- Original message -------------- <BR>> From: Budd Engineering <JERRY@BUDDENGINEERING.COM><BR>> <BR>> > Yep, and I couldn't be happier. <BR>> > <BR
>>
> True R/C 2500 mAh LiPo's, $30 each, fits inside the 10X <BR>> battery holder <BR>> > with a minor amount of trimming with the Dremel tool. I bought <BR>> one <BR>> > set to try, liked it so well I bought another and converted <BR>> the spare <BR>> > battery pack. That way I can charge them out of the <BR>> transmitter (not <BR>> > that it matters, the charge rate is so low that the risk of a <BR>> mishap <BR>> > is about the same as with NiCads or NiMh). <BR>> > <BR>> > I screwed around with a couple sets of NiMH's for the past <BR>> several <BR>> > years, they were a total waste of time, the self discharge <BR>> rate got to <BR>> > where I had to re-charge them if I didn't fly within a day or <BR>> so of <BR>> > the previous charge <BR>> > <BR>> > The LiPo 's pea k up at 12.5 V, essentially the same voltage <BR>> as a good <BR>> > set of NiCads, and discharge almost
linear
ly, so it's easy to <BR>> assess <BR>> > their state of discharge. <BR>> > <BR>> > http://home.comcast.net/~truerc/ready_pack/ready_packs.htm <BR>> > <BR>> > Thx, Jerry <BR>> > <BR>> > Budd Engineering <BR>> > jerry@buddengineering.com <BR>> > http://www.buddengineering.com <BR>> > <BR>> > On Sep 22, 2008, at 8:56 AM, vicenterc@comcast.net wrote: <BR>> > <BR>> > > Has anyone done the conversion? <BR>> > > <BR>> > > Thanks, <BR>> > > <BR>> > > -- <BR>> > > Vicente "Vince" Bortone <BR>> > > _______________________________________________ <BR>> > > NSRCA-discussion mailing list <BR>> > > NSRCA-discussion@lists.nsrca.org <BR>> > > http://lists.nsrca.org/mailman/listinfo/nsrca-discussion <BR>> > <BR>> > _______________________________________________ <BR>> > NSRCA-discussion mailing list <BR>> >
NSRCA
-discussion@lists.nsrca.org <BR>> & gt; http://lists.nsrca.org/mailman/listinfo/nsrca-discussion <BR>> <BR>> _______________________________________________ <BR>> NSRCA-discussion mailing list <BR>> NSRCA-discussion@lists.nsrca.org <BR>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion </BLOCKQUOTE></body></html>