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Well for what it is worth I was able to duplicate the original problem almost down to a degree of what Lazun originally reported with both a R6014FS AND a R607FS rx on the bench just a little while ago. I used a heat gun and a Raytec IR temp gun to measure temp as it increased. Within a degree of each other they both "went red" at 167-168 degrees. I was able to "reboot" them around 150 deg. Both these rx are brand new (a few weeks) and were still in the box. I bound the R607FS just for the test. The flip side of this is that the 6-7-8ch receivers have been out now for a while and I don't remember hearing anything at all regarding any type of loss of signal in the air. Maybe it happened but I don't remember hearing about it(except for the service bulletin issued by Futaba some 6-7ch tx having the same coding or ID). I am honestly thinking that there is enough air flow through the fuse that the rx should be cooler in flight than on the ground. I am thinking about getting a Venom temp gauge like we used to use in heli's to record the peak temp on the rx. I am also thinking about how I can increase cooling to the rx. Perhaps a CPU fan and some sort of ducting for outside air to be channeled over the rx. I am not sure yet.
Now for those that are getting ready to say go get Spectrum...not so FAAST (couldn't help myself here...lol). A friend of mine, who is in the R/C electronics business, has actually disassembled and examined the spectrum satellite rx and taken the information right off the the chip and found per the manufacturers spec on their very own website that the chip is only rated Commercial (not industrial) and is good up to 70C or 158deg F. He has mentioned that customers have called him and mentioned the they have had a lockout or binding issue with the Spectrum setup but could not duplicate it. It is possible that they are suffering from a thermal issue as the Futaba is.
Here are the specs on the Spectrum chip he sent me. By the way..I am not trying to bash JR, just trying to pass on some info that may be helpful.
The guys at Spektrum use this chip CYRF6936-40LFXC in
every satellite receiver they sell.
This is a commercial temperature range chip, 0C-70C. See
page 31 of the data sheet attached.
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We'll, if you could get hold of some Thermal Compound and a piece of Aluminum plate, you might try rerunning your tests with the RX sitting on the plate (with compound between the plate and the bottom of the RX) to see if the still RX craps out at the same temp.
It might advance the state of knowledge while waiting for Futaba.
Of course, a big metal heatsink in the vicinity of the 2.4Ghz antennas might not provide a flight solution.
It is possible that the component/components that are quitting are part of a bad run and the design is not at fault, or it could be that the combination of ambient temp/radiated temp absorption and internally generated heat (probably from the processor) go beyond the design limits of the RX.
I imagine some heavy duty processing is occuring to handle all those channels plus the frequency hopping algorithms etc. Thats gotta generate a lot more heat than simpler receivers (I think), assuming the same type semiconductor technology is being used.
Ira