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Radio went dead mid-flight

PostPosted: Fri Oct 04, 2013 5:05 pm
by loopy
Hi

I was flying my pitts biplane using my turnigy 9x/ frsky JR one way module radio when I lost the link to the model which went into failsafe and subsequently crashed.

While this was happening I looked at the screen and it had gone blank but the backlight was still working.

Immediately prior to the loss of signal I had tried to use the rudder trim. The radio made a series of rapid beeps as if the trim button was working , screen went blank and the beeps continued until I turned off the radio after the crash.

After the crash I turned off and re-started the radio which now seems to be fine. I have not managed to get the radio to fault again on the ground so am hoping for suggestions as to what may have been the cause.

The second thing is the pins on my radio seem to be a bit short and sometimes the module wont transmit unless I push it really hard into the radio. Is there anything I can do about this?

Please note. I feel the 2 problems are unrelated as when the module loses contact the screen is still ok.

Would much appreciate some suggestions as I prefer this radio to my futaba 6xas and don't wanna go back.

Cheers

Geoff

Re: Radio went dead mid-flight

PostPosted: Sat Oct 05, 2013 7:55 am
by BillGriffiths100
The unexpected reset with the horizontal trims is due to a hardware fault in the 9x, it came to prominence when people put a larger capacity microprocessor in the 9x for increased functionality they discovered that the new processors were more vulnerable than the ones with the original chip to this problem.
But some (a very few) of the originals are affected by this and yours appears to be one of them.
There is a fix to which cures the problem read the following thread carefully especially the two last pages when we come to the best final solution. Don't cut any wires!
http://openrcforums.com/forum/viewtopic.php?f=95&t=3594

Re: Radio went dead mid-flight

PostPosted: Sat Oct 05, 2013 5:40 pm
by loopy
Bill!

Thanks very much. That is the exact problem I had. I will try reading the fix a few times then attempt it.

My radio runs the stock firmware and is powered by a 3 cell 2200 lipo.

Its gutting that a standard radio should have this problem but that's the story of my life lol.

Thanks very much for your reply.

ps. Has anyone got a fix for the poor module connectivity (short pins) problem?

Cheers

Geoff

Re: Radio went dead mid-flight

PostPosted: Sat Oct 05, 2013 6:46 pm
by BillGriffiths100
Hi Geoff,
Do the pins coming from the back have a raised plastic bit around the base in the TX back moulding?
Some of the early 9x's had that and it prevents modules other than the original sitting properly, that was dropped by version 2 radios.
If so you have to remove it but to be honest I don't know how (because I've never seen one in the plastic), probably have to remove the board from the back of the radio, then cut away the surround with a file.
Otherwise the cure would be replace the short pins with long pins in the pc board, or perhaps shorten the stand-offs behind the board a bit to allow more of the pins to poke through.

Re: Radio went dead mid-flight

PostPosted: Sat Oct 05, 2013 11:11 pm
by loopy
Thanks Bill. I'll try cutting the projection off then.

I did the other mod as you suggested and the trims all still work so I assume it was a success....

I appreciate your help :D

Cheers

Geoff

Re: Radio went dead mid-flight

PostPosted: Mon Oct 07, 2013 2:46 am
by cynr100
Trimming the plastic away is the common solution, just be careful and patient. Helps if you have a Dremel tool.

Re: Radio went dead mid-flight

PostPosted: Thu Oct 10, 2013 7:15 am
by tedbmoss
Note that in addition to the above (I use a soldering iron to melt the plastic) if your module connection pins are too short, it could be that they have come loose from the back board of the tx and need to be re-soldered and epoxyed in. That's what I do with all mine.

Re: Radio went dead mid-flight

PostPosted: Thu Oct 10, 2013 10:33 pm
by loopy
Awesome guys,,,,,,,thanks for all your help.



PS Can I get anybody in NZ to reflash my radio with ER9x??

TA

Geoff

Re: Radio went dead mid-flight

PostPosted: Fri Oct 11, 2013 8:17 am
by BillGriffiths100
Have a look at this post there is someone on it in NZ
http://openrcforums.com/forum/viewtopic.php?f=95&t=315

Re: Radio went dead mid-flight

PostPosted: Sat Oct 12, 2013 11:02 pm
by loopy
A quick question Bill........

I did the alterations as per the diagrams on the wiki site which was linked from the open RC thread and when I went to set up the aircraft I couldn't get the throttle or rudder to work (both were at max travel even though sticks were neutral, so I went back to the original article and cut the trace as shown there and now its all good. Can you confirm I have the right way.


I did this to get it going...............

Image

it now works

Previously I had done this and it wasn't working.............

Image


I haven't cut/joined the orange wires at all.


Does that make sense :roll:

Cheers

Geoff