Dwaine

I was wondering what li-po to use? do i use a resister?
Adam Drake uses them for both. Sounds like a good idea. please help

piper_chuck

My Feedback: (12)

you need a voltage regulator. However, given the issues with lipos, I would never use them in a plane or a transmitter. Lithium Ion, maybe, but not lipo.

Gulliver

According to Don Schulman, all transmitters have a voltage regulator that will handle 15v. I have been running a 3-cell Lipo in my Futaba 9C for a couple of years now with no problem.

Running receivers over 6v is problematical, however. You need a regulator and preferably a 2-cell lipo pack.

Wlouigene

My Feedback: (66)

I have been running a 3-cell Lipo in my 9303 with no problem and all my plane and heli have lipo
http://www.grandrc.com/inc/sdetail/50357
http://www.troybuiltmodels.com/LiIonBatteries.htm

JNorton

My Feedback: (2)

Given the fact that at least once a season I either leave the transmitter or a receiver pack on I'll stick to my NiCads! Do it with a Lipo pack and you'll be replacing it. I usually only fly for 4 hours or so at a time so the longer life the Lipo pack offers doesn't matter to me. The ability to put the pack on a C/10 charge for 16 hours and have it perform like new is worth the extra weight. I'm only a sport flyer so I don't care about shaving a few ounces off the airplane. Your mileage may differ.
John

PS Gulliver
Given todays cost cutting programs I certainly wouldn't take that advice to the bank. I'm not saying your 9C doesn't have a built in regulator but I certainly wouldn't give it a blanket statement like that.

Wlouigene

My Feedback: (66)

You need to be careful; you would not leave your stove on for a season, why would you leave your receiver on. I know these things are toy but you need to be careful with them as with anything else

JNorton

My Feedback: (2)

Bad analogy. A stove gives off heat. Pretty darn obvious that you left it on, yet people burn their houses down doing it. Nothing shows if you leave a transmitter or a receiver on. If you haven't done it you will. Obviously if I leave only one or the other on in a 4 months time frame it's not like I'm not being careful. Besides I don't own any toy airplanes. At $400 to $2000 a copy it more like an obsession than a toy.
John

PS EDIT -> Ever leave a basement light on all night? It usually happens when I'm shooting the bull with some of the guys. It interupts my routine and I forget to turn the darn thing off. Usually at the end of the nights flying when I run the fuel out and start the engine up to clear it of any left over fuel in the tank.

pilotpete2

Hey John,
If the new Sanyo Eneloop cells are as good as some are saying, then we may come to the day when if the question is raised of using lipos in a Tx, it will be met with, You want to do what??!!

rmh

the 2.4 DX7 tx comes with a large NiMh--will fly all day - yet people persist in putting in LiPos - go figure
I left my DX7Tx on - (what else is new ). plugged the ol wall wart in - the next day back in business-- no issues .
as for the rx -- 2 A123 cells beat anything power wise, weight wise, reliability and instant current -no reg needed.
but
having a setup which will "run all weekend" means more to some - even if the reg or cells go up in smoke
What's up with that?

Rafael23cc

My Feedback: (6)

All of you missed the point that the original poster is a car racer.

If that even matters to some of you. Some of your points are valid, some of your points do not apply as not all radios are made the same, specially car radios.

Rafael

JNorton

My Feedback: (2)

What difference does having a car transmitter or receiver bear upon the fact that a LiPo will be toast if it is left on? Not trying to be a smart a** I just don't see the differece?
John

Rafael23cc

My Feedback: (6)

You ask:
I said:
Why would you argue?

I just wanted to bring the discussion back onto subject. RC Car radio subject.

Rafael

Panzlflyer

My Feedback: (15)

I think A123s for the car....although the original poster is far from specific
I use Eneloops for the transmitter (Car)as they stay charged as advertised and the usual 1500 in my DX7.

Rafael23cc

My Feedback: (6)

He was specific enough:
If you rub elbows with car racers you know who Adam Drake is. Just like if you rub elbows with heli pilots you know who Alan Szabo and Curtis Youngblood are. Quique Somenzini comes to mind when you say airplanes.

Doesn't matter, let's go back to the subject.

Rafael

piper_chuck

My Feedback: (12)

Gosh, how could people have missed something so obvious?

Dwaine

i get the point though everyone. thank you.. planes or cars if i forget, i'm buying new li-po's.
Does enypone know if there is a programable failsafe. so i could choose the voltage cutoff..
I think the spectrum transmitter has one but i'm not sure..

Dwaine

I'm thinkin of building an hpi savage out of as much carbon fiber as i can find.
I was thinkin of ways to save weight. thats why i was wondering about a single cell li-po.

JNorton

My Feedback: (2)

LMAO Car forum http://www.rcuniverse.com/forum/forumid_201/tt.htm
The point was whose points are valid? I'm certainly glad you realized it was a car question. I sure didn't. I sure don't understand the electrical power requirements ie differences between car and plane transmitters either. Course I'm only an EE and didn't spent the night in a Holiday Inn either.
John

Rafael23cc

My Feedback: (6)

Me either, that is why I was watching this topic.

People here were talking about Futaba 9C and 9303 that are without a doubt more complex radios than a car radio. As to how they work internally I have no clue. All I care is that I have control over my helis, airplanes and cars when I flip the switch. Be it from a LiPo battery, a NiCd, a NiMh, or a LiIon.

If anyone has problems with leaving your radio turned on after flying, that person needs a better safety check list than what you have right now. I bet that that person has had some full throttle starts or radio off starts too. Need I say that in helicopters, that is particularly dangerous?

Rafael

rmh

You have never had these things occur ?
Fly long enough - it will happen.

Rafael23cc

My Feedback: (6)

Many years ago, I had one hot start on a heli after I switched from a JR servo to a Futaba servo. They have their movements reversed.

After that I sold the 30 sized helicopter and got myself a 50 and a 90. Those will get your attention real quick. If not, irreversible damage could occur.

Knoing that, I'm pretty cautious on the way I do my pre- and post flight checks.

we are strying away from the subject at hand. What was the concensus? You could do it on the TX, but on the RX you need a regulator, right?

Rafael

rmh

why not ?
in for a penny
in for a pound-
My own feelings?
NFW

pilotpete2

Very true, and while were on the topic of leaving a Tx turned on "got simulator", Getcha real easy.
Pete