radio failure-my experience

as i have faced radio failure, i want to present all that i have been into, and comments from experienced fellows.
i imagine this is a controversial issue, so i ask you fellows to follow it and reach your own conclusions.
will keep adding stuff, as i have it scatered and sometimes is hard to retrieve, so please keep coming back AND SEE THE UPDATES AT THE END.
i started having problems at a field where i flew for several years. for some time it was isolated loss of signal. then suddenly the bottom fell. the field has nearby 4 towers from the local radio station.
lets start with this:
https://www.rcgroups.com/forums/show...e-Interference
https://www.rcgroups.com/forums/show...o-Interference
then when asking experts, i got this:
Originally Posted by SkyNorth
How is the Internet being supplied in that area.?
Where I live , WiFi signals are beamed from a central Tower to small dishes on our roofs.
Is it possible a new provider has installed in your area, or picked up a couple of customers
that would require them to "beam" across your flying area?
there is also this comment from David E. Buxton :
High gain antennas for outdoor Wi-Fi are also a concern. Lookout for these antennas and don’t fly through their beams.
https://www.google.ca/webhp?hl=en#hl...w+does+it+work

more: got this:
Can you take all your systems including the good and the bad to another field? Try the following at a different field.
You may be exceeding the ability of the ESC BEC to power all the servos. You may have switch mode bec interference. You may have RF interference from the surrounding transmitter towers.
First I would make up a separate receiver pack for test purposes preferably NiMh or if you have to use a LiPo use a linear ubec i.e. no switch mode interference possible. Second I would make sure your Rx antennae are mounted so that the bare ends are outside the aircraft and at right angles to one another.
1) do a range check on each one moving all the controls as you do the test. You are looking for acceptable range. Only you will know what you normally get for each system.
2) depending on the results instal your receiver pack and see if there is an improvement in range. This could eliminate ESC BEC as the cause of your problem either due to high servo current demand or a BEC switching frequency problem.
3)depending on the results fly the worst performing but acceptable range system and see if the problem still exists.
If it all went well and all the systems performed OK then go back to your own field, do range and flight tests and see if the problem still exists. If it does then you may have to find a new field or buy better radio gear.
The local club had a field which is in an area near an Iron and Steel works i.e. Blast Furnaces Electric Arc Furnaces, Rolling Mills etc. We had a black spot in the days before 2.4 GHz radios where occasionally members inexplicably crashed. It was either reflected radio transmissions from our club house and shed or radio interference from the Steelworks. We never solved the problem until 2.4 GHz radios were invented.
Working on a high accuracy high speed roll forming and punching machine we had inexplicable errors in the distance measurement system. When hooking up an oscilloscope to the end of the long cable from the shear we found a high frequency standing wave induced in the cable whilst it was unpowered. It came from a transmitter tower about 1 km distant from the factory. This induced HF voltage roughly corresponded to our switching frequency at certain roll forming speeds and was proven to be the cause of our problem.
If you can not get to a different field try this:
From my experience the most robust system is FrSky. If you can borrow a FrSky module and a receiver plug it into your 9XR Pro. Program it to announce the RSSI every 15 seconds - it will annoy you but just for testing it will be very valuable and then do a range test. ( You can carry the Tx and observe the RSSI reading on the 9XR Pro as you walk away from the plane) Then do a flight test to see if it will cope with your field conditions, listening to the RSSI announcements. Test how far you can fly in each critical direction before you get RSSI readings which are too low i.e. less than 45. You will then know whether the adjacent transmitters are the problem and whether FrSky gear will be a satisfactory solution.
Steve
at the time things seemed to be fixed, i got this:
from Nigel: Glad to hear of your success. It agrees with a discussion I had with John recently. Both of us think that the two types of Lemon receiver (which share the same front end) may by virtue of the sensitivity that gives them excellent range be particularly susceptible to swamping by a very strong nearby transmitter such as you have at your field. We also think it is entirely feasible that changes at the broadcast transmitter could make a difference to its impact on your receivers; these could involve changing the broadcast pattern or some other aspect of transmission.
Your latest report seems to support the idea that other receivers are less susceptible. So you may have a solution to your problem.
Regarding the Lemons, this tends to support their excellent reputation in nearly all situations but does suggest that they may not be a good choice for use near powerful broadcast transmitter towers. It doesn't mean they are prone to interference -- that's quite different from swamping.

these are the details on the crashes when i was using the orange rx:
may 16, 2013: i have been using my orange radio with great success for several years. so much that i ordered another 1 (that still have not used yet).
but 2 days ago (may 14), and today again, 3 of my planes crashed. battery was fully charged-and the receiver too.
the 1st 2 went like this: launch and after 20 seconds loss of signal and the plane dove vertical. the last 1 today was climbing and then did not respond to a change in direction neither stopping the motor. kept climbing. then after i turned it down, waited 10 seconds and turned it on-nothing. several times, until suddenly went into a spin and dove vertical and crashed. then today (may 16) i used another radio (9xr pro) and all went well.
(this was at the beginning of using the pro). but then it began to fail too. and even worse: even at another field-something that other radios didnt-neither do-at another field.

and since i moved to another field (far away from the 1st-and no antennas-radio or otherwise), the problems are gone.
zero. zilch. go figure.
just in case: what is wi-fi?
http://time.com/3834259/wifi-how-works/
so could be that the farmer nearby got wi-fi, or the radio station did some tune-up, but the only way i have been able to fly without radio problems was moving to a far away field.
when 2.4 started the revolution, it was said that from then on we all could fly at the same time without interference.
it was with DSM. but then, when there were several planes in the air, and more radios on the ground with the owners doing some adjusments, we began to loose signal now and then. that is why DSM2 was released to take care of it, so they said. it was the DX6i that has this. i used it for some time-i dont remember if i had any problem-that is until 1 day my planes began to fall. it was when i flew at the field near the radio towers, so i moved to another about 30 km away, where it has not happened anymore.
>>>conclusions: while still wondering why all of this happened, i noticed that sometimes the screen was blank at the moment of picking up the plane after landing, so i went through the whole system, and noticed that sometimes when touching the individual cells that i used in the transmitter this happened again, so i replaced them with packs welded from factory, and it didnt happen again. this made me rethink about the whole situation and decided to risk my planes again at the field of the towers and since then, all is well. which makes me think that my problems were a combination of weak contacts-and the powerful towers having some sort of adjustment to their signals. notice that i say 'weak' contacts' and not 'false' contacts. it is the only logical explanation. the combination of the mighty towers and those weak contacts! vagaries of electronics! but beware of individual cells in your transmitter.
>>>sep 25, 2017: an update: after some flying at the towers field, i began to experience loss of signal and erratic behaviour again. i also noticed that the vario, that is independent from the radio, also had some lapses where didnt send any height or tones. this made me think that could be another factor. at the other field id started at 10:00 due to the regulations. here i can fly any time, thats why i flew as early as there is enough light. so, could be that at the other field all was o k because from 10:00 something in the weather makes things work fine?
so i checked humidity, and sure thing, early it is very high! and sometimes even later it is very high too. anyway, at the end of the day i fly later and all is fine. i also consulted at the radio forum and got some confirmation that waves are blocked by humidity.
so if you find yourself in the situation of getting erratic signals or loss, check humidity. some days even not early is very high, but does not seem to be to influence the flight. so much to learn!