Problems!! 14MZ 2.4 R6014FS

[Jurgen Heilig]

	Quote: Originally Posted by lazun
	Here is the information found on the R6014FS 2.4 receivers: ... Air Temperature at time of test 82°F TIME (PM) TEMPERATURE (Left/Right) TESTS and FINDINGS 12:52 Rx 84*F / 84*F turned both receivers on with aircraft in shade 12:54 Rx 92*F / 92*F on in shade 12:56 Rx 94*F / 94*F on in shade 1:07 Rx 98*F / 98*F on in shade 1:12 (20 min.) Rx 99* / 100*F on in shade 1:15 Rx 100*F / 102*F on in shade ...

If above data is correct, the heat does not come from outside (ambient temperature 82°F), but from inside the rx. The current consumption of a FASST rx is 10 to 20 times higher than a conventional PPM rx.
At 5V and 80mA, we are talking about 0.4W in heat losses. Enough to heat up the R6014FS by about 9°F in 10 Minutes. After that, the condition remains stable, i.e. no further increase in temperature. What was the voltage in above situation, where the rx temperature increased by 16° F in 20 minutes?

Jürgen

[grayuk]

We would expect the rx to be hotter than ambient, and looking at the figures, worst case was 20degF.
The rx only reached 102F which is nowhere near the 164 F needed for a failure.
The additional thermal energy is coming from outside the rx to make it fail.

As far as the UV/Light goes, that would not explain the heat gun failure.

[OnTheEdge]

	Quote: Originally Posted by Jurgen Heilig
	If above data is correct, the heat does not come from outside (ambient temperature 82°F), but from inside the rx.

If this is the case, then someone should be able to duplicate 164F by just hooking up 10-12 digital servos and wiggling the sticks for 20 minutes in the workshop.

[crhammond]

Judge - I did actually test a number of devices last night. I tested the 5014Rx, 319 synthesized PCM Rx, Multiplex IPD and for good measure I tested them again while hooked up to a Powerbox and a Smart-fly.

My test rig was a shoe box on its side (to trap the heat a bit better.) I did not blow air directly on the equipment - I used the heat gun from a couple of feet away. I used an IR temp gun on the surface of the electronics once they failed to get an idea how hot they were. I figure that by heating them slowly the board is "around" the same temp.

Not very scientific - but repeatable. The only items that did not work were the FASST Rx's. Everything else was working fine at 200f and up. FASST shut off somewhere between 130 and 160 and turned back on between 100f and 90f - much faster if you turned off the heat and blew cold air in.

Like Paul said - in a cool climate you're likely okay. Inside a camo warbird on a sunny day or under a clear canopy - well I'd be careful. And if it's 100f outside - look out IMO.

I'm not trying to put the cart before the horse. Futaba needs time to test this for sure. Ut since some people are flying in warm climates best to spread the word. By the way - I only did my testing because I thought this was a hoax. It is not. Anyone with a heat gun should be able to repeat this for themselves. I have a lot invested in my Futaba gear and I am not interested in causing a bad name for them - I love the equipment and it has been rock solid. So far very few people have seen this in "real life. "

The bench test is easily repeatable on all my Rx's which have been bought over a 1 year span.

I am not ready to take mine out since we don't have hot weather yet. But I will be monitoring them carefully and keeping the canopy covered.

Paul - thanks for the info and picture. I also have mine installed similar in an electric and nitro pattern plane. I am trying to understand why the install is more sensitive (in terms of failsafes) in my bigger aerobatic planes. I am wondering if it might actually be the CF prop and gear. That would certainly make some sense. Anyway - for whatever reason, when they are mounted with the antennas up in the canopy there are no issues with signal.

[gregorycstitt]

Again the Judge has to interject his personal opinion like we are all out to destroy Futaba. I have always and will continue to fly Futaba but lay off those of us that are having problems. You want facts here's your f--- facts. I purchased a NEW 12FG radio 35 days ago. Fact! My plane was built by a professional who has built planes for Chip Hyde, and Quique. Fact! I flew my Python 5 times and now, in the heat, lost signal between the receiver and the transmitter over 9 times. Fact! I have checked the DURALITE voltage regulators and the batteries and all are wotking perfect. Fact! I am not running some super power box or cans. Fact! I haven't flown in three weeks and I am still waiting to receive my radio back from Hobby Services. Fact! These are not internet reports, these are my FACTS and 5 pilots saw me lose signal. One other fact, you are anyoing a lot of regular pilots who use this site to gain information and knowledge, to help in making sure all of our equipment is working properly. If you believe I am making these stories up to slam Futaba or gain some advantage then you are full of S---. I'd rather not have these problems and just fly. But the fact is, with my 2.4 system I cannot right now. So there's your F--- facts.

[JimC-MD]

For anyone that does not think that a "thermal load test" in the field is a valid diagnostic technique, you have never been in the position to try diagnosing intermittent problems. Both heating and cooling of electronics to reproduce a concern are valid. Sure, a lab is a more controlled environment, but the symptoms can and should be the same. What you will find in a lab with an engineer is the exact component or connection that is causing the failure.

Heck, percussive testing (fancy name for tapping) and the wiggle test can be right in factory testing charts.

Here is the reality. The way the internet can have issues distributed to many more people in a compressed time shortens the threshold time for investigation. I think there is enough information here for Futaba to persue and they are. They will not get as much exercise RUNING down dead ends and JUMPING to conclusions as we can here. That is a good thing. They will be very methodical and see if and what the resolution is. The time compression is good because we could go through months of NPF (no porblem found) until some piece of information comes out to help create a verification test. The hard part is the patience needed to let a good solid evaluation and resolution come out.

Everyone needs to relax and let a good company, with a good reputation work it out. The questions that have been asked on this thread (both those that seemed like hangmen and those that seemed like defensive linemen) are the exact types of questions that will go around the engineering department with people that are in a better position to find the answer. To those that took the time to come up with a field test that can help point the way, again I say kudos. New let's just chill a little and wait for the answer.

JimC ( a JR owner that understands his stuff is not perfect and throws noone under the bus ) I hope this post sounds unbiased and supportive of all, as that is how I intended it.

[rcflyer]

By now, Futaba Japan should have some initial findings to report.

[Judge]

	Quote: Originally Posted by gregorycstitt
	Again the Judge has to interject his personal opinion like we are all out to destroy Futaba.

No actually I was wearing my Mr. Science hat. The idea is to isolate variables among equipment. Now it looks like it is the Futaba FASST RXs versus other Futaba and Multiplex non-2.4 RXs that have a heat issue.

This appears to eliminate non-2.4 from the equation.

So now the question is will a JR/Spektrum do the same thing? Answering that question will help determine if it is perhaps something in all 2.4 electronics, like chips, board size, etc., or if it is limited to just the FASST. All this helps narrow down the root cause and is important information.

I am mystified why that enraged you. I assume it is because you failed to grasp what I was trying to say.

Here's an amusing story. When I worked in the oil industry we used electronic logging tool in the wells to gain information about the rocks. Heat increases with depth and it eventually gets to the point where the tools fail from the heat.

So Schlumberger and others have special "hot hole" tools. I thought these were specially engineered and tested, etc. I asked how they did that. The engineer told me this:

"We bake them in an oven until they fail. Then we replace the failed part and bake it again. We keep doing that until we no longer have to replace any parts".

Heat is a killer of electronics for sure.

Now once Futaba isolates the cause of this issue then the next question will be is it ALL FASST RXs, just some models, and possibly even a certain lot. Maybe there was a run of bad chips or something. It happens. And since some people have shown that their 6014s can take the heat, it just makes it more complicated.

I hope none of this irritates you.

[BR289]

The possiblity of there being a bad run does change things a bit...I can see that happening. The bottom line is that people have had similar experiences and that warrants an investigation through Futaba in my opinion.
I guess I am hoping they isolate the problem to a bad batch of chips rather than having every receiver recalled or something.

[bgold]

I know heat is the enemy of electronics. Should the fusalages have a few holes in the first former as well as holes in the tail to allow for air movement and cooling of the inside and electronics. Does anyone think this would be detrimental.

[crhammond]

	Quote: Originally Posted by bgold
	I know heat is the enemy of electronics. Should the fusalages have a few holes in the first former as well as holes in the tail to allow for air movement and cooling of the inside and electronics. Does anyone think this would be detrimental.

Yes you bet they should be vented. And so far unless I missed something - the lockouts are on the ground. When I flew my Python the temp ont he Rx's was significantly lower after landing which I attribute to good air flow. BUT if it is 100f+ outside that may not be enough.

I too would like to see some Spektrum/JR stuff heat tested. I don't have any of it so I can't test it...

[emessys]

A short, philosophical interjection.

Human progress (?) is dependent on those who are willing to be on the cutting edge. My hat is off to you.

But whereas being first up the ladder from the trench may lead to Fame and Glory, its not so good an idea if your goal is to lead a long, peaceful life and die of old age.

So if you want to be on the leading edge, you have got to be prepared to pay a price, and cant complain if things don't go as hoped.

Forty years of experience in the electronics business have taught me that it is always the customer who discovers the problems with the shiney new toys.

It isnt that the manufacturers are incompetent, duplicitous or venal.....they are just trying to get a product to market in a limited time frame where they dont want to be blindsided by their competitors. Thats business. There isnt the time, money or people to check every possible contingency.

The final product testing is done by the purchaser.

So it is entirely up to the end user to decide if they want to be the guinea pig for any new product, and whether they can afford the potential downside. Caveat emptor.

So again, my hat is off to those in the forefront, but blowing your stack is not seemly.

[AEROCOLOR]

Emessys comment should end this discussion unless someone can provide a solution or test results. Period. We are all experimenting with new technology every day of our lives. Please stop the negative comments and bickering. It causes me shame to be associated with the hobby and what brand wars do to people. Grow up guys!
Bill

[Judge]

	Quote: Originally Posted by BR289
	The possiblity of there being a bad run does change things a bit...I can see that happening. The bottom line is that people have had similar experiences and that warrants an investigation through Futaba in my opinion. I guess I am hoping they isolate the problem to a bad batch of chips rather than having every receiver recalled or something.

I hope that they can actually duplicate this on their bench. If not, then it REALLY get messy.!!

[grayuk]

Looking at all the info, it does seem that the FASST 2.4rx failure is the issue.
So, as has been said, where do we go from here?
I agree, the next step is to see if this is just a Futaba FASST problem or generic to all 2.4 systems.

We may be surprised!

If it is not then the Futaba engineers will have to pinpoint the failing device, unless one of us has the facilities to use localised cooling on a failed rx.
You can buy cans of ‘freezer’ which is used in electronic fault finding for just this type of problem.

Raise the temperature till the failure occurs, then selectively cool individual chips until the offending part is found.

One guy who may have the equipment to do this is a German guy called Julez.
He has done a lot of extensive FASST testing and has access to some great equipment.

I have emailed him and asked him to pop over to this thread, he may be able to help us take this further while we wait for Futaba to resolve it.

Paul