single battery possible?
 

is it possible to get away with a single battery setup for ignition and receiver?

i read in another forum (quote) "if you are fly 2.4 ghz, they can be the same battery as long as you use 2 separate leads."

if so, what should i look for. rf-noise?

???

RE: single battery possible?
 

Here is Futaba's advice about the matter.
http://www.futaba-rc.com/faq/faq-gas.html
I'll attach JR's and Hitec's response.
The answer is "Don't do it".

RE: single battery possible?
 

I have been using a 3cell LiPo with reg supplying power for RX(2.4) and Ign on my gassers for over 2years with no problem. I use ferite coils on the power lines.

Cheers

RE: single battery possible?
 

I use 1 2300ma A123,1 switch,1 remote kill {RCexll}6 HT/Digi MG servos pluged into 1 futaba 2.4 rec,never a problem.

RE: single battery possible?
 

Several persons do it and have had absolutely no problems so far, but do you feel lucky. If my radio manufacturer says, no don't do it, I'll only give you one guess as to what I would do, but as they say, to each his own. It really comes down to your choice but safety should come first, and to use one less battery and risk the possibility of losing your model....well.

Karol

RE: single battery possible?
 

Well said karol. Dan.

RE: single battery possible?
 

Actually CAN be done and SAFELY...

Put in a WIKE IBEC .... (can be purchased from Troybuilt or MagnumRC)

Not only does it TOTALLY stop *any* type of 'noise it also give
an added feature of TX engine kill w/o using carb...

Run direct from RX to ign, set end points at 100/100, set to a switch... DONE...

Works on 2.4 or 72...

RE: single battery possible?
 

1* 3000mAH 2S Lipo. 1*8A switching regulator (cost £10). 1*3A switching regulator (cost £4).

Corona 35M receiver (about £10). 6 digital servos and 26cc CRRC pro with Melody ignition in my 70" Yak.



Absolutely no trouble at all. Wish I had ditched the 5 cell 4300 nimh and 4 cell 2100 nimh ages ago! [8D]

RE: single battery possible?
 

Look for??? Maybe a extra airplanehttp://www.rcuniverse.com/forum/js/f.../msn/47_47.gif

RE: single battery possible?
 

as long as the plane is fitted with a battery packof sufficient capacity and capable of high current draw, the ignition and Rx circuits are isolated then whats the problem?

Fear tempers progress but not always with good reason

RE: single battery possible?
 

Why would you?

My ignition battery, booster circuit and switch are 31 grams total.

If you stated power requirments for your reciever and servos we could suggest a light weight and reliable combo for there too.

RE: single battery possible?
 

Ok so on my DLE 20 engined TWM Spot On I'm running Hyperion LiFe packs of 1600mAhr for the servos and Rx and the 1700mAhr for the ignition through a diode,

I use 120 mA.hr of Rx+Servo current per 10min flight time and 100mA.hr of ignition A draw.

I'm pretty sure I can get away with 2x 1100mA.hr LiFe Packs. or one 2100mA.hr pack.

RE: single battery possible?
 

I tried using a 5 cell 2000 NiMh pack with a single lead and ran into what turned out to be a "brown out" condition with full elevator or aileron input. There were no other issues (on mine). I added a second power lead and switch to the same battery and was able to get a couple of short flights out of it prior to running into that same brown out issue. Added a second battery and problem was gone.

OMP 67" fusion/DLE 20/Aurora 9/5 digital high torque servos

FWIW

RE: single battery possible?
 

two issues are being discussed

1. is rf noise passed thru battery?.. the answer is no, just go as the engineers at apc or the likes the battery absorbs the spikes and noise.

2. 200ma nimh dont have enough amperage output to supply the draw of the digital servos and ignition, lipo and life batteries do....
why would any one use nimh in this day and age is beyond me, they cost more do less and fail often, as well as having much shorter lifespan, and weigh more, and cost more.

RE: single battery possible?
 

http://s1.postimage.org/ux14icgl3/pg0427_lg.jpg

RE: single battery possible?
 

Agreed.


PS: 3600+ NimH (anything sub C or bigger) does work, is reliable enough and will not brown-out, but why bother as they weigh lots!

RE: single battery possible?
 

i have been running a OMP 80" profile with a BME44,with one 2300 a123 for both rx and ignition.
the ignition side is regulated down to 5.5 volts,on 2.4 rx.
been flying it for two years now with out any problems,BUT i still won't use it in any of the bigger stuff,just to be safe.

RE: single battery possible?
 

I'm agreeing with the bold (while noting we're talking about 2000's). My note was an attempt at illustrating how that decision was made - in case others were headed down the same path. It was certainly not intended as a "how to", but more of a "how NOT to" - but I thought that was obvious?

My biggest lesson had to do with the fact that the NiMh batteries pretty much suck when it comes to supplying amperage when compared to about any other battery type commonly used in RC. Despite their popularity with the guys I fly with, and the fact I consider myself fairly well read when it comes to RC (though admittedly not a fan of all the electronics), I missed that fact - which became the latest in the list of "stuff" learned the hard way....

I did see where the NiMh sub C packs would do the job. I looked at the weight of the sub C's (almost the same as 2 AA packs) and decided I preferred the redundancy of the second pack. I had the 2nd pack in stock, and the second switch had already been installed, so I went that way.....this time. This new education in hand, I won't be buying any more NiMh - but I'm not going to throw them all away either....

RE: single battery possible?
 

I have one NiCAD pack and the rest are LiFe.
I figured that current delivery was important very on but simply looking at the impedance of the packs and battery chemistry.

Then observing that most folk having battery trouble used NiMH and those who did not were using LiPo's on regulators.
Where theres smoke there's fire I guess.

Now back to flight packs for gassers. I've still not seen a convincin arguement that running onelarger capacity pack is bad. Failures of LiFe or LiPo packs under low drain is fairly rare I guess but even so they're more robust compared to NiMH. </p>

RE: single battery possible?
 

For small airplane applications (60-120) where this discussion makes sense, one could use lipo + regulator for the receiver and/or ignition, to save a few oz.

Thunder Power Pro Lite v2 790mah: 1.6oz
Thunder Power Pro Lite v2 480mah: 1.2oz

Pick the regulator that has the proper capacity rating (e.g., 5A for non-3D fly).

RE: single battery possible?
 

3 50CC planes. 1 2200 Mah A123 battery with dual outputs and with an ignition drop down on each. Hundreds of flights total.

No problems.

Spektrum DSM2 and DSMX installations but I'd do it with any name brand system.

RE: single battery possible?
 

I have my 30cc Yak setup with dual 1100 A123 packs and separate switches to the receiver, ignition is powered from the receiver by a Wike IBEC. I've never used 50% of the capacity of the packs.
I have an old Goldberg Extra 300 (BIY kit) with a 20cc and run just a single 2300mAh A123 pack for receiver and ignition. Never a problem. As I understand it, the lower the internal resistance of the battery, the more it acts as a filter to any voltage spikes.
For any size glow powered model, even a .90 or better, just pop in a 2S A123 pack of 1100mAh and go fly[8D]
Pete

RE: single battery possible?
 

yeah with the A123 ot LiFe packs I can't see a problem running one battery pack of sufficient capacity.

In fact thinking about it deeper, its probably best to run 2 x 1100mA.hr LiFe packs into the Rx and power the Ignition from a BEC as this provides true battery redundancy.
With one pack for Ignition, and one for RX theres still the chance of losing the plane if the RX battery dies.

In fact its much safer with the BEC because if the circuits are separate and the RX battery goes off line you better have an opto kill swithc in there that will kill the ignition as well. Without it your plane is going on a long flyaway.

The more its discussed , the better tha IBEC powered Ignition seems.

RE: single battery possible?
 

Lots of people run this setup with their Smartflys with no problems.
I run my scale gassers with a Lipo 5000MA and a tech-aero.net system and 14 servos with no problems. The servos are not the hi-draw type.