Futaba fasst 2.4ghz signal loss
 

I was flying my slow quickee plane last week to make sure is was ok for our local club race when all of a sudden I had no control. I was using the brand new fasst 2.4ghz system and was not expecting this at all. I inspected all the servos from the wreck and they are all in good shape and none of the control rods, horns, or hinges had come loose. I remember someone having about the same experience with the spektrum radio. Does anyone know if their are any problems with these new 2.4ghz radios?

RE: Futaba fasst 2.4ghz signal loss
 

no heard of any.......

all connectors still good? what battery and what was the voltage of the pack?

RE: Futaba fasst 2.4ghz signal loss
 

I checked the battery voltage, and it was a ok.

RE: Futaba fasst 2.4ghz signal loss
 

There are hundreds of these systems in use, and many satisfied pilots. I'm a Spektrum flyer myself, and have not had a single problem to date, with likely well over 100 flights at multiple flying sites. This is the first reported "crash" of a Futaba system I've run across.

The important thing to remember with these systems is to check your battery under load (plug in a volt meter and watch the voltage as you try to move your flight surfaces by hand to simulate air flow while flying). If the voltage drops too low (either due to the pack being dead or because the pack is too small for the model) it will shut the receiver completely OFF. (No mushy controls or soft lockouts like FM, here it competely STOPS working).

Use the right battery, make sure no servos are binding or stalled, and just fly it. The 2.4 GHz stuff available really works good, and it doesn't really seem to matter who's brand it is.

Adam


I can't resist a good jab at brand F though: "Superior full range technology" What gives? It sounds to me like they crash just as good as everybody elses stuff does from time to time.

RE: Futaba fasst 2.4ghz signal loss
 

Strange as it seems --
The idea that if you check a battery before using -then after using-you will then know how it performed under use -
not so -and was never so

older systyems were fairly non critical of low voltages
these microprocessor system require power within limits
The Spektrum is really no worse than the others, tho some yip about tenths of a volt differences -all of em will quit -somewhere in mid 3 volt range--according to all published spec.

IF your power system is such that depressions of voltage can reach under four (4) volts -under any working load - you - have - a- problem-- jest a waitin to happen.
Just like a computer - if power fails -even for a split second - the system must restart - whether it takes .1 seconds to reset or 1 second - it still has to do a reset.
one more thing - higher voltage batteries and regulators do not prevent the problem from occuring.
electric powered models have shown to be most suseptible to the power problem, due to the many combos of cells/esc/bec etc., in use.
some are no good - some overheat easily etc..

RE: Futaba fasst 2.4ghz signal loss
 

The crash was a q500 with 3 standard servos one mini servo and a standard 4.6volt hitec receiver pack. Nothing on this plane should really have put that much of a load on the battery, its not like a 3d plane. Maybee I should play it safe and go with a 6volt battery, but I hear that pulls the battery down faster.

P.S. I thought our battery testers put a load on the battery to get an accurate reading?

RE: Futaba fasst 2.4ghz signal loss
 

It really depends on what type of tester you have. Some do put a load on the battery, most do not.

Also, you need to make sure the battery was put into service properly. A new pack needs to be cycled (charged slowly, then discharged fully) to format the cells. Sometimes a battery might appear to be good, but the capacity isn't what the numbers on the cells say it should be. Cycling the battery with a battery charger/cycler will give a much better understanding as to what the condition of the battery really is.

With the new 2.4Ghz equipment, I really tend to shy away from anything smaller than a 1000 mah pack. The batteries these days are getting smaller and lighter, and finding a pack with that capacity in a small size and weight isn't a big problem anymore. The small 600 mah packs that come with transmitters or RTF planes are worthless. Anything needing a battery smaller than 1000 mAH usually has a BEC in it anyway... Which brings up a whole new line of trouble.

RE: Futaba fasst 2.4ghz signal loss
 

You would be surprised at the amp draw of servos trying to deflect while flying at high speed

RE: Futaba fasst 2.4ghz signal loss
 

I've starting using the Hobbico quick charger with a built in battery peak charge cut off. Could this be related to my problem, maybe with this set up I never conditioned the battery.

RE: Futaba fasst 2.4ghz signal loss
 

If you think 4.6 volts is a standard voltage for a 4 cell pack, I respectfully suggest that you read up on NiCad an NiMh batteries.
With fm and ppm radios low voltage means your plane will act strangely. With the 2.4 radios your plane will look strange in the field dumpster.

I regret to admit that the vast majority of pilots have very little battery knowledge and give their batteries very little attention, except charge and fly.

Most people in my club do not cycle their batteries. At least half don't own a loaded voltmeter.

This is all going to change with the 2.4 systems. I'm afraid this is going to cost a lot of pilots an aircraft to get their attention.

The phrase at the field I like the least is, "It'll probably be OK."

RE: Futaba fasst 2.4ghz signal loss
 

4.6 is a depleted voltage reading on a 4.8 pack - (never saw a 4.6 pack)
but then 4.8 is also a depleted voltage on a 4,8 pack

here is a guessing game
:
On a fully charged then mildly exercized 4.8 pack- what do you think the lowest operable voltage would be
lets make it easy
let's say a 1100ma 10 mohm impedance pack
Now what if we add a one amp load - what should it show for say 5 seconds
now let's try a 2 amp load ?
OK- can you make these tests with what you have?

For those who don't have funds for lots of test equipment - here is a inexpensive way to do it .
buy an On Sale Harbor Freight VTVM (a voltmeter) maybe 5 bucks
also buy a 1157 tail light bulb from any auto parts place .another buck or so
take some old extensions and solder up a Y adapter so you can plug a battery pack into one socket and the VTVM and the tail light bulb into the other one
I have added a picture of some A123 batteries under a two bulb test - which pulls about 3.5 amps

With this rig - you can discharge cells - test sells etc.. all for a very low cost.
any guy with some electrical background can help you with this - it is really 101
with a couple of bulbs and an amp meter (again, cheap) - you can become VERY well informed on what your batteries will do under use with the larger loads imposed by the higher torque servos .

RE: Futaba fasst 2.4ghz signal loss
 

Randy's right. and I plead guilty myself. But since I made the move to 2.4 gig I pay a lot move attention to my batteries. If you do a lot of fast charges the cells will be out of balance, and a peak charge may not be a full charge on all cells. The volt meter only shows volts not whether or not each cell is fully charged, your ma may be half of the battery rating.
I fly 40%. I have three planes each with four batteries. I now use the charger-cycler that Randy makes. It will do four batteries at a time. Once a month I plug up one plane on Sunday night and do two cycles and two C-10 charges, the rest of the month I fast charge. When I fly the next Sunday I can see the ma that came out and the ma that went in.
Is his charger cheap, no, is it cheaper then my H-9 Ulitmate, yes. See for yourself at Hughsrc.com. Dennis. PS Randy is Flying Geezer

RE: Futaba fasst 2.4ghz signal loss
 

Nothing wrong with your system Dick. The problem is that most guys won't do it.

Probably the best thing we can do is encourage the "I just wanna fly" guys is to use large 5 cell packs and get a device to test capacity. There is cycling equipment on the market for as little as $70-$75.

You don't see the "I just wanna fly" guys on the radio or battery forums until they lose an aircraft, and don't have a clue.

Even then, another "I just wanna fly" guy has filled their heads with a myth that's hard to dispell.

I just watch and try not to laugh.

RE: Futaba fasst 2.4ghz signal loss
 

H-9 has a new volt meter out that can load the battery from .5A to 2A HAN171. also they have a digital servo&receiver current meter. Plug this one in between the battery and receiver and read the current draw and your plane. HAN172. Dennis

RE: Futaba fasst 2.4ghz signal loss
 

If you put the Hobbico Voltwatch on your plane, it will provide some good info. Make sure it is plugged into one of the spare channels on the receiver (not on a Y connector) and look at the display as you cycle the sticks. If you see the LEDs bouncing around as the sticks are pushed, you may have a problem as that means you are getting voltage depressions on the receiver bus. If this happens, you are in need of heavier duty wire, better switch or batteries with less internal resistance. Also, if you check the Voltwatch at the end of each flight before turning off any switches, you will have a good idea of the state of charge of your on board battery. The Voltwatch is almost as good as having an ocilloscope on your battery bus.

RE: Futaba fasst 2.4ghz signal loss
 

[quote]ORIGINAL: Flying Geezer

Nothing wrong with your system Dick. The problem is that most guys won't do it.

yes - I know that -
having been around long enough --I see that most attempts to encourage a little self help-are simply wasted efforts.
My attitude is shifting into the "that's too fu-king bad " answer catagory when I get questions such as "why did my plane crash?"
The other thing that bugs me about the " techno gap" , is the flyer who assumes that because he has loaded the inside of his model with all the trick batteries and regulators -strapped around the rx , he has a safer system
when in most cases - he has created a Frankenstein setup that simply blocks signals or is highly susceptable to heat failures.
My own findings with the 2.4 stuf I use is that a extremely simple approach works very well
rule !- for a reciever pack use either A123 cells or new , conditioned, Nimh low impedance cells and include an on board Vmeter which you can watch -at any time to se if any servo is pulling excessive current
very very simple.
2 follow steps in rule 1
for electric models - place rx away from any other FREDS on the model and on any model with more than a single 2100 ma single pack - use a outboard Switching BEC which is MATCHED to possible servo loads
finally -pretend th 2.4 radio is th pilot (it is ) and place the rx in the canopy so that it can seeout.

RE: Futaba fasst 2.4ghz signal loss
 

HI LIBBY..........

RE: Futaba fasst 2.4ghz signal loss
 

Yes, it gets like series xmas lights.

My biggest concern in the switch over is a Raptor 50 chopper. I have hungry digital servos and a good size battery pack. If I go to a 5 cell pack for extra insurance i'll have to use a regulator because my gyro won't handle a 5 cell. The regulator is of course another link in the chain of failure, and I think a re-boot in a heli would be even worse than a re-boot in a fixed wing.

I'm going to have to study this a little.

RE: Futaba fasst 2.4ghz signal loss
 

Oops, I was meaning to say 4.8 volt.

And please don't call me Dick, maybe just slightly insensitive ;)

RE: Futaba fasst 2.4ghz signal loss
 

Lost me on that last line.

RE: Futaba fasst 2.4ghz signal loss
 

My filaments don't glow so good anymore either.

RE: Futaba fasst 2.4ghz signal loss
 

Mine is long gone, but I still have a Simpson 260 in a closet somewhere. Dick is gettin' older by the post.

RE: Futaba fasst 2.4ghz signal loss
 

at last - I get some sort of respek
but my post was intended to make someone -anyone - think -about how/why servos/batteries operate together ..
Sorry I won't make that mistake again.
Next time I will simply suggest a Vote meter
perhaps that is a more familiar term.

RE: Futaba fasst 2.4ghz signal loss
 

oh, thats ok, just a a bad joke.

RE: Futaba fasst 2.4ghz signal loss
 

Don't apologize I think this a great topic for people getting into the 2.4ghz stuff. It really sucks to loose a plane for any reason, other than dumb thumbs.