Problems!! 14MZ 2.4 R6014FS

[Judge]

Post #193 makes exactly the case that I have been talking about. Oh well. We have no facts, only internet reports. But those are as good as facts for most people.

I wonder if anyone has taken a heat gun to their transmitter, or powerbox, or anything else. I sort of wonder how they hold up to extreme heat.

Also, I am waiting for somebody to try the same "test" with other types and brands of receivers or devices. It would be very interesting to know how other RC electronic devices/brands hold up to the heat gun test.

[grayuk]

	Quote: Originally Posted by crhammond
	Just for fun I took a 5014 PCM Rx and started to "cook it" with my heat gun. Now there is no link light on PCM... so I hooked up 1 single servo. I got that case as hot as I dared (240f - thats past boiling point right?) The servo still moved fine after 2 mins of super heating - the case was hot enough that touching it would burn your hand (not much but you would for sure feel it.) I have been doing my testing on Rx's outside the airplane with no servo plugged in at all. Just a 4-cell pack (around 5 to 5.2v nominal.) I did a 607 Rx - this time I kept the heat gun far back and heated slowly. It took quite a while but eventually it went red too. And it stayed red until the case was barely warm to the touch. This one went off at a much lower temperature - the case was only around 130f. I measured my cases on Monday in the plane after sitting in the sun for 10 or 15 mins. It was maybe 70f outside and the cases were at 121f. When the red light comes on you can CLEARLY hear something go "click" in the Rx and the same when it comes back to green (on the 6014.) On the 607 I didn't hear anything. Now I am a little worried. I will for sure be putting a cover over my canopy from now on though and I will keep an eye on things with my temp gun in case I am wrong. With air moving through the fuse the Rx should stay cooler - but letting it sit in the sun seems like a big risk. Maybe something as simple as a white case that reflects heat vs. the black heat absorbing case would be better in a hot climate? Gray - you fly jets right? How warm does it get inside the fuse? Have you ever seen any failsafes having the Rx mounted inside the fuse? I find it odd that an Rx burried inside a jet fuse would be okay and yet on my planes I seem to need to get the antennas up into the canopy... If I could put the Rx's away from the open canopy I know they would stay a lot cooler.

Yep, I fly jets and aerobatic models.
I have had no heat issues but to be fair…I live in England and we don’t get that many really hot days.

Thanks for the test on a standard rx, that tells us that it is definitely only the 2.4 rx that is ‘giving up’ at t a lower temp.

My RX in my Hawk sits under the canopy but down below the full depth detail.

I have no RX sitting under a large canopy directly.

To the best of my knowledge we have no reported issues else where in the world apart from the USA in the hotter climates.

Jets may not suffer the problem, (depending on installation) because we have a turbine sucking a lot of air from everywhere and it may cause more air movement in the fus than you are getting.

I have also done extensive testing with carbon, metal and fuel. None of these proved be a significant blocker of the signal.
The tests included placing an rx inside a metal tailpipe, inside a carbon fuselage. I got little or no deterioration of ground range.

I have tried to enclose a picture of my Hawk install.

Paul

Just found this interesting thread.
FASST vs. 3 Watt video transmitter

[RH1N0]

I notice there are a few posts suggesting that the Rx is more susceptible to failure when mounted under the canopy. The current assumption is that this is due to extra heating but there may be another factor - the direct sunlight itself!

Many micro SMD voltage regulator data sheets have warnings against exposure to direct sunlight such as this text from a typical National Semiconductor chip:

Exposing the micro SMD device to direct sunlight will cause
misoperation of the device. Light sources such as Halogen
lamps can effect electrical performance if brought near to the
device. The wavelengths which have most detrimental effect
are reds and infra-reds, which means that the fluorescent
lighting used inside most buildings has very little effect on
performance.

The FAAST RX's look as though they have a semi transparent case which may not provide a great deal of IR protection. So perhaps the IR exposure is affecting the REG or maybe even de-rating it's thermal protection specs.

Note that this is just a suggestion and only intended as food for thought for those who are doing some testing. Good luck

[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.