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serpa4
12-07-2005, 11:07 AM
Any way to do this safely? New TX doesn't have a diode. Tx is 9.6 volts, 3 cell is 11.1v. However, after a full charge, my Tx is 10.5-11 volts I think. I'd love to charge my Tx in one hour with my lipo charger.

Red Scholefield
12-07-2005, 12:23 PM
Any way to do this safely? New TX doesn't have a diode. Tx is 9.6 volts, 3 cell is 11.1v. However, after a full charge, my Tx is 10.5-11 volts I think. I'd love to charge my Tx in one hour with my lipo charger.

The end of charge voltage 12.6 volts of a three cell lipo might be more than your transmitter can tolerate. You would need a regulator to drop it to 10 volts.

Matt Kirsch
12-07-2005, 01:01 PM
Now, do you want to charge your transmitter's battery with the LiPoly charger, or do you want to put a LiPoly pack in the transmitter?

As Red indicates, putting a LiPoly pack in a transmitter really isn't practical. Charging a "roundcell" pack with a LiPoly charger isn't practical, either...

If your transmitter doesn't have the diode, you can use any adjustable-current peak charger designed for NiCd and NiMH packs. I normally use my $35 Hitec CG340 to give my transmitters a boost during a long flying day.

Rugar
12-07-2005, 01:10 PM
We have a club member that's been using a 3S pack in his Eclipse TX for about 6 months now. Has not had any problems with it as of yet. I like my Optic 6 to much to gamble on it.

Unbalanced prop
12-07-2005, 04:22 PM
There is a company that is selling lithium packs for transmitters. I can't comment one way or the other on them, just supplying a little info.

http://www.commonsenserc.com/commonsenserc/product_info.php?cPath=27&products_id=32

Doug

serpa4
12-07-2005, 06:33 PM
There is a company that is selling lithium packs for transmitters. I can't comment one way or the other on them, just supplying a little info.

http://www.commonsenserc.com/commonsenserc/product_info.php?cPath=27&products_id=32

Doug

Exactly what I was looking for. I'd love to have the 2500 capacity, no memory, and be able to a no self discharge tx pack. I could then use my Lipo charger to charge since it doesn't do anything but lipo. Keeps the field equipment down to a minum, and less to lug around when camping also, just TX, heli, handfull of batteries, and charger.
Its a bit pricy though.
I've also considered the radioshack battery holder and a set of the quick, 15 minute charge, 2500 mah NiMh batteries and charger from wal mart for I think $20 or so. Nimh do self discharge a significant amount after a few days. And I have to carry a little charger around that only runs on A/C.
Anyone know if I could charge the lipo pack above through the charge port on the Tx? Sounds posible, voltage is voltage, and the charge part should be handled thorught he charger and not the Tx. If the tx allows for quick charging, it should work. Let me know your thoughts please.

Jacket Man
12-07-2005, 10:31 PM
serpa4

Most of the guys using our 2500mah pack in their TX cut the connector off the charger that came with their radio and splice it onto thier regular LIpo charger. Or they purchase our inexpensive ($13) wall charger and splice the connector on to it.

Feel free to call me if you need additional info.

Toll-free 877-709-3835

Mike
www.CommonSenseRC.com (http://www.CommonSenseRC.com)

http://www.commonsenserc.com/commonsenserc/product_info.php?cPath=27&products_id=32

serpa4
12-07-2005, 11:37 PM
My LHS said that a fully charged 3Cell would be too much voltage. I also take it I have to watch for battery to reach 9.0 volts since the TX meter will not know its Lipo.

Jacket Man
12-07-2005, 11:45 PM
Your LHS is incorrect. There are lots of us using 3 cell lipos in TX's. Here is one of many guys using them.

http://www.rcgroups.com/forums/showthread.php?t=439858#post4576571

He is correct that you have to pay attention to the voltage, but given that it is about 4 times the capacity of the standard TX battery, oyu don't need to check it that often. Like many aspects of our hobby, you have to watch the details.

Matt Kirsch
12-08-2005, 02:50 PM
All transmitters have some form of voltage monitoring, and computer transmitters automatically shut off when the voltage drops below 9.2V. Provided there's no voltage regulator artifically raising the voltage, if you stop flying before you hit the "red zone," you won't come anywhere near the 9.0 cutoff on the pack.

Best practice is to recharge after a flying session. There's no harm because the pack has no memory, and that way, you're always ready to go.

Rugar
12-08-2005, 03:07 PM
All transmitters have some form of voltage monitoring, and computer transmitters automatically shut off when the voltage drops below 9.2V. Provided there's no voltage regulator artifically raising the voltage, if you stop flying before you hit the "red zone," you won't come anywhere near the 9.0 cutoff on the pack.


My Optic 6 doesn't even sound the low battery warning until 8.9v

GeraldRosebery
12-08-2005, 06:51 PM
Any way to do this safely? New TX doesn't have a diode. Tx is 9.6 volts, 3 cell is 11.1v. However, after a full charge, my Tx is 10.5-11 volts I think. I'd love to charge my Tx in one hour with my lipo charger.

No problem, but consider using LiION, they are safer to charge in the transmitter. I have used a 2100 mah 3 cell 11.1V LiION pack for over a year now and can fly all day with no problems. A warning - never let the pack discharge below the 3V per cell. Make sure that an LED lights when you switch on or one day yoU ARE going to leave it on by mistake and that's the end of the pack. The huge advantage is that you can charge today and use the transmitter 6 months from now and it will still be chanrged!

serpa4
12-08-2005, 07:42 PM
Yes, one of my considerations for LiPo, charge now fly later. If I get to the field and its dead, I can use my lipo charger and fly quickly.

A10FLYR
12-09-2005, 05:07 PM
No worry about leaving the switch on in the upper end radio systems. They have a programmable automatic shut-off. Mine is 10 to 30 minutes if no stick movement is dectected.

Red Scholefield
12-09-2005, 07:02 PM
No worry about leaving the switch on in the upper end radio systems. They have a programmable automatic shut-off. Mine is 10 to 30 minutes if no stick movement is dectected.

Which ones would these be? I note the Futaba 14MZ boasts a lithium battery for 3 hrs flight time, but I didn't note any auto cut-off feature. Could have missed it.

LuckyArmpit
12-10-2005, 04:10 AM
What I did was buy 1600 mah nimh panasonic cells from the local Big Lots.
An 8 cell pack that I soldered up and put on the connector was $8.
I run it on my Futaba 9C and get almost 4 hours of use out of it before I charge it on my triton. Been running it now for almost 2 years. Alot of places will charge ya $25 or more for a tx pack that size. Cheaper if your handy with a soldering iron.

Dave...

Gullwing
12-11-2005, 03:48 PM
Ok maybe a dumb question. I have been thinking of the Lipo battery in my TX for awhile now. I have an Optic 6, is the programming memory on it a flash type system or will I loose programming when I disconnect the battery? I was thinking of just getting a larger mah battery but I have 6 aircraft programmed and I don't want to reprogram all them again. ..............GW

Jacket Man
12-11-2005, 08:44 PM
All the computer type radios retain the model memory when the battery is disconnected.

Mike
www.CommonSenseRC.com

everydayflyer
12-11-2005, 09:04 PM
I am sure LiPolys are great in Transmitters if you never forget and leave it on by mistake,it does not mind have voltage over 12 volts applied and if you reall need a battery which only self discharges approximately 5% per month and do not want to have to charge your transmitter more than once or twice a year due to the fact that you hardly ever fly and never have any idea when you may fly next time. Also remember that LiPolys are more easily damaged by high temperatures than NiCads or NimH cells so they should not be left in a vechile in warm weather.
I have used high capacity AA NiMH cells for years and some of my test data is listed below.



Data from a 23 days delayed discharged test:

Sanyo AA 2500 mA HR charged 23 days ago.
Under a 300 mA load 10.25 volts.
Discharged on Triton at 500 mA rate, approx. twice Transmitter drain.
165 minutes to reach 9.3 volts. (last test 193 min. fresh of charge)
187 minutes to reach 9.0 volts capacity 1,580 mA to here.
This is 343 mA less capacity than when tested fresh off of charge.

18% capacity lost during 23 days of storage.

12-2-05 Extended Storage Test

Sanyo 2500 NiMH AAs (green sleeved industrial variety) charged 5 weeks (35 days) ago. Transmitter not in use and had only been turned on a few times to check voltage display.A total of 5 minutes on time during past 5 weeks.

Starting voltage today 10.2 Volts.
5 addational mintes on time 9.8 volts.
30 addatiaonl minutes on time 9.6 volts
60 minutes on time 9.6 volts.

test stoped and Transmitter back on the shelf.

To me a NiMH battery which was charged 5 weeks ago and still hold at 9.6 volts under the real load of a Hi Tech Eclispe 7 Transmitter after being on continuesly for 60 minutes is very good performance.

12-09-05 Week # 6 update.

Transmitter back on volts dispalyed 9.9 after five minutes.
At 30 min. 9.3
At 90 min. 9.4 volts ( Transmitter was in a 60F room but brought into a 72F room for test.)
Turned off for 60 minutes.
Turned back on 9.4 volts.
9.3 volts after addational 138 minutes.
Total on time during the past 7 days (week 5 and 6) since charge 300 miniutes and voltage holding at 9.4 volts.

Charles

Gullwing
12-11-2005, 10:53 PM
Thanks Mike, I figured they would retain the memory but didn't want to take the chance..........GW

roccobro
12-14-2005, 07:30 AM
I gave up trying to find a cheap, high cap lipo or li-ion pack that would fit and give me what I was looking for. I ended up getting some Energizer 2500 cells for $18 and rarely have to recharge. I am too cheap to pay for the little weight loss, and couldn't find a high enough capacity pack (until just now) to even match the Energizers.

Justin

serpa4
12-14-2005, 03:35 PM
I also like the convenience of just one charger. I have a DC charging staion in my grage, so I dont even need A/c any more. And, when camping without AC, it no problem. Otherwise I'd have to carry a converter around with my field equipment.

cyclops2
12-14-2005, 06:42 PM
Is it really wise or safe to have LIPO packs strapped around your neck or that of a kid and have a short then flash fire in your face?
That is similar to walking around in a combat area carrying a handgrenade with the pin pulled.
If you do not care about your own safety. How about those all around you ?
LIPOS should only be active in the vehicle. Away from people.
Go over to RC GROUPS and read their LIPO fire accounts. More power to them. Know the risks before OPERATING something as if it were a harmless toy on a string.
Edit:--- Do not due the range check with someone holding the plane at full throttle. Use the holding stakes in the ground.

serpa4
01-05-2006, 06:16 AM
Why fly with LiPo, you are endangering everyone around you. What if they explode in the air? Then you have a balistic bomb. I try not to drive anymore because 10s of thousands of people die in car accidents every year. More people die in car accidents than from LIPO fires yet we still drive every day.

Is it really wise or safe to have LIPO packs strapped around your neck or that of a kid and have a short then flash fire in your face?
That is similar to walking around in a combat area carrying a handgrenade with the pin pulled.
If you do not care about your own safety. How about those all around you ?
LIPOS should only be active in the vehicle. Away from people.
Go over to RC GROUPS and read their LIPO fire accounts. More power to them. Know the risks before OPERATING something as if it were a harmless toy on a string.
Edit:--- Do not due the range check with someone holding the plane at full throttle. Use the holding stakes in the ground.

John Benns
01-05-2006, 10:47 AM
Well this is an interesting topic but, should'nt we be more concerned about the pack in the airplane rather than the pack in the radio? Radio lets u know when the pack is low. Simple solution is get a second tx pack. Is'nt it? never seen an exploding pack yet. Seen some cool fires caused by bad esc choice. Ahmm.

ragbag
01-05-2006, 02:27 PM
We were afraid of fire when we first saw it.

Made our steaks taste so good we put up with the chance of a fire or two. We learned to control it and still burn down our houses and pastures.

Look at the people in Texas and Oklahoma. They must use a lot of lipos there.

We will always have the naysayers in car racing or gun shooting or lighting your barby grill.

Go Git them Bulldog!!!!:D
By George

t. edwards
01-05-2006, 07:03 PM
Hi, I run a sanyo 9.6v 1450mah nimh pack in my JR XP6102. The extra capacity over stock is very nice. Lipo's would be great but I have been known to screw up and not get my tx turned off. The nimh's can deal with that but it would kill a lipo. The tx does not shut itself off. Happy flying, Tom

Jacket Man
03-27-2010, 07:30 PM
We've added a balance connector and multiple discharge connectors to broaden the number of brands that this pack is "plug 'n play" with.

Mike
www.CommonSenseRC.com

roboto65
03-29-2010, 01:27 PM
I have a 10C and have been using LiPos for a few years in my TX have had no problems. I have a 2500 Commen Sense in my 10C right now and have had it in there since the TX was brought out of the box. I had a 9C before that and it also had a LiPo.

Oh and my first post here Hi All:cool:

rea59
03-29-2010, 01:59 PM
I have a 3S lipo in my DX7 and in my JR Sport SX600. Been using them about two years now and I fly often. It's great to be able to fly for a month without recharging and then when I do recharge it's very quick and can be done at the field. The key to using Lipos is to remember that your voltage will stay up there till almost the end of the pack. I recharge usualy at about 10V and find I've used 2000mah out of a 2500mah 1C pack.

cliffh
03-29-2010, 02:41 PM
Interesting thread. I must say, I have NEVER seen a lipo "just explode". The only damaged/burning lipos I've even heard of were the very early ones, lipos that have been in a very hard crash, or lipos that have been very badly overcharged. They DO NOT JUST EXPLODE. Geez.

Many cell phones, computers, GPS units and on and on have lipos inside. Do you really think the lawyers and insurance companies would allow these to be used if lipo's "just exploded" in use?

Besides, nicad's can explode if shorted. So can nimh batteries. So can your car lead/acid battery and it is right in there with gas lines nearby.

I'm not knocking anyone for trying to be safe, but lets please stay real with this.

If anyone is concerned about their transmitter being strapped to your neck and exploding, do not use a strap! Simple. Toss that sucker when you hear it start to hiss or what ever it does just before the exposion.

Cliff