Flysky 9x only turns on when a trainer cable is connected

[remondo]

Hi,

I've just found my Flysky 9x transmitter after a long period of inactivity however it will not turn on unless I connect a trainer cable into the audio jack on the back. I have tried with and without module connected that came with the transmitter. I've checked all switches are in their neutral positions. When the trainer cable is connected, the transmitter appears to function as it should but without the cable, the power switch does nothing and the screen is blank.

Am I forgetting something or could it be that there is an issue somewhere?

My 9x is fitted with the now discontinued smartieparts 9x Solderless Programmer Board and flashed with er9x. I also fitted a backlight from hobbyking. The transmitter has worked in the past but has been sat dormant for close to a year. When I found it again, the lipo was swollen so I disposed of it and have just received a replacement which has been fully charged and shows as 10.4V on the transmitter when the trainer cable is connected.

Cheers

[jhsa]

open the TX, and make sure all connectors are fully inserted. specially the 12 way connector that comes from the back of the radio and the 6 way connector to the right of the LCD connector..

João

[Daedalus66]

Pretty clearly a main switch or associated connection failure, unlikely to have anything to do with any other component such as SmartieParts board, module, etc.

The trainer setup is designed to behave as you describe. With the Switch OFF plugging in the cable applies power to the transmitter but not the RF module. In your case, even when turned on the switch is not supplying power.

For now you could try spraying contact cleaner on the switch. If that doesn't do it, you will likely get more specific advice from the experts.

EDIT And at that moment João appeared!

[remondo]

Thanks, I'll open it up later and have a look around.

[jhsa]

Nigel, I am not an expert, far from it.
I just happened to see a lot of these radios. I have been learning a lot with all the good people from this forum. Everyday I learn something new that I keep until I can use it to help someone else.. it's great you do the same as well, so you know what Im talking about.

João

[jhsa]

Thanks, I'll open it up later and have a look around.

Yes, and please report. Then we will go from there..

João

[remondo]

I've just had a look inside and think I've isolated the issue down to the 2 metal prongs which make contact with the PCB on the back section. See attached photo. Judging by the less than ideal design of this connection, I'd bet that this is a common issue. I should probably also mention that one of the prongs has somehow snapped at the very end where it forks into two, leaving only one side of the fork but I can't see how this would affect the connection.

I've bent the prongs to try to apply more pressure when the case is closed and the TX does then power on. However, the slightest knock on the casing causes the TX to power off. Subsequent knocks on the casing cause the backlight to flick on and then instantly off again.

Any suggestions to remedy this?

I now realise my post is in the wrong section of the forum but I had assumed this to be a software issue at first, sorry!

Thanks again

[jhsa]

That piece of metal should not have effect at all.. I removed it on all my radios..
Did you check the connectors?

João

[remondo]

Oh! Well it must be another connection then. I'll have another look around but yes I did check the connections I could see.

[jhsa]

I've bent the prongs to try to apply more pressure when the case is closed and the TX does then power on. However, the slightest knock on the casing causes the TX to power off. Subsequent knocks on the casing cause the backlight to flick on and then instantly off again.

Is this with the power switch ON or with the trainer cable connected?

João

[Daedalus66]

Just to confirm that I too have removed the metal piece. If the radio lights up when it makes contact, that just shows that something that should be connected isn't. Because it's connecting back of the Tx to the front I would look very closely at the cable that links them and at all associated wires and connectors.

[remondo]

I've bent the prongs to try to apply more pressure when the case is closed and the TX does then power on. However, the slightest knock on the casing causes the TX to power off. Subsequent knocks on the casing cause the backlight to flick on and then instantly off again.

Is this with the power switch ON or with the trainer cable connected?

João

That's with the power switch on. Perhaps it was checking all the other connections that temporarily fixed it.

[jhsa]

Ok, it looks you have a bad connection somewhere. I think it might be close to the switch board because the radio works with the trainer power. That means the connection on the big 12 way connector should be ok. Ok how did you install the backlight? Did you use the original backlight plug?
So the backlight plugs on the mainboard and the connector coming from the switch board connects to another backlight connector?
If this is that case, please disconnect the backlight and connect the switch board connector directly to the mainboard again. See if the problem is still there.

João

[remondo]

Thanks again for the reply. I just had a good look inside, took a few connectors apart and checked the soldering to the backlight and something must have been loose because it seems to be working fine now! Thanks for all your help!

[jhsa]

Don't fly with the radio yet. Remember, you didn't find the problem.. give it a good test before you attempt to fly a model with it.

João