I need a stock 9x main board.

[tigar]

Hi.
After a mishap on my radioi am left with a dead board.
I am looking for a stock 9x board to fix my radio.
Please let me know if here is one for sale.

[ReSt]

What's dead with the board ?
Why not try to fix it ?

Reinhard

[ShowMaster]

I agree, fix it!
Pictures of your board and what you know happened to kill it? Is it stock or modified by you in anyway? Details please.
Any chance the tx battery got reversed, very common condition.
SM


Sent from my iPod touch using Tapatalk.

[tigar]

After messing with the voice, it stopped responding. While it can be flashed, I have no display. All mods and connections removed preparing for a investigation but it won't hurt looking for a new one...

[jhsa]

check all, the resistors..

[tigar]

What you mean?
The resistors to the display?

[jhsa]

yes. also a good idea to check if you have power going to the display.. I think it might be 3.3V.. see if there's also 3.3V at the regulator.. the one on the left.

[tigar]

The regs are checked both 3.3 and 5v

[jhsa]

See if you can check if power get's to the display.. be carefull not to short anything..

[tigar]

I did check whatever i could think of. power to display, resistors, continuity to atmel pins, shorts, different lcd...
still no display.

[jhsa]

another display?

[tigar]

I tried another LCD...

[jhsa]

After messing with the voice, it stopped responding. While it can be flashed, I have no display. All mods and connections removed preparing for a investigation but it won't hurt looking for a new one...

Messing with the voice could have caused something to fail..
It's just an idea, but maybe looking for shorts in the little vias (both sides of the board) where the wires for the audio board connect.. check that there are no damaged resistors as well.. hhmmmm, maybe I'm repeating myself here

[tigar]

All LCD visa checked from atmel pins to the top of the upper resistors line. All show the same resistance. Can't remember the value.

[jhsa]

hhmmm, the way I see it is that if the atmega is working.. and the LCD is not damaged, then the problem is somewhere in between. that leaves the power, and those resistors and little tracks and vias

Unless the atmega is working but some pin is damaged?? could an oscilloscope be useful to find that kind of problem? If so what kind of signal would we be looking for on the different pins??

João

[mbanzi]

I have one transmitter in the same state, although my problems didn't start after the voice mod, but the upgrade to the m128. It was working fine until (I think) I plugged in a FrSky module - turned on, no display! Transmitter still works, just has no display. I tried a different LCD, checked for shorts, blobs of chipquick, burnt components, even backed out all mods. Spent hours on it and eventually gave up and ordered a new transmitter...

[jhsa]

it would be interesting to scope it and see if the atmega got damaged or not..

[rperkins]

yea. write a little piece of code that sets all the pins to outputs and toggles them on and off. Upload it to the MCU. then even if you dont have a scope you could use an led. Most of the pins already have a resistor attached to them. just put one end of the led to ground and the other on the far side of the resistor. There's even a thru hole on the pcb board in that location. Of course I'm just thinking out loud and this may not be feasible

[tigar]

it would be interesting to scope it and see if the atmega got damaged or not..

I can send the board to you to investigate if you like.
I hope I can found a replacement...

[jhsa]

I have not the right equipment or knowledge to test it.. otherwise I would be glad to do it and help you..

João

[kaos]

Have you 'double' checked the display ribbon connection? that happened to me yesterday after the encoder mod. everything works except no LCD display, found out it the stupid ribbon was not fully seated.

[rperkins]

So can you actually fly a model with it ? Do you get a PPM output at the simulator plug or module bay pin ? is it completely working but without a display ? I was thinking maybe the fuse values got changed. It'll accept an update over SPI, but the timings are wrong to drive the display, or anything else.

I have no idea if EEpe checks or updates fuse values when programming

[kaos]

I believe there is a place you can set fuses in eepe. But I try to avoid that part.

I have not 'fly' one yet.
I have a set of D-series rx/sensor/servo laying around. each time I have done something, I just hook it up to see if telemetry/ppm/servo is working or not. After your question I powered on one of my planes already bond to the DJT module and it works - on the ground. That one has a V series rx, so telemetry was not tested on that plane. The telemetry was tested with the set up I mentioned.

[mbanzi]

There is hope!

I spent a few more hours debugging my transmitter today. Symptoms were no LCD display, but transmitter was fully functioning. I was able to use it by selecting the default model in companion9x & flashing the eeprom. After doing the M128 mod, the LCD would stop working sporadically then eventually stopped working completely. When the LCD did come on, the transmitter would reboot frequently.

I checked for continuity on all pins, as well as from the other side of the resistors to the pin on the MCU - nothing wrong! Eventually out of frustration (and I have a spare 9x on order), I pushed down on the M128 and noticed the LCD would come on again! I realize by pushing down on the chip's pin when checking, I would have good contact and therefore couldn't find the disconnected pins.

Solution was to to clean up the pins using solder braid, then re-soldering using lots of flux. Works perfectly now. This was the 2nd M128 mod I did, so I guess I wasn't as careful as when I did the 1st one! Lesson learnt...

[jhsa]

you used the drag soldering method on the second one if I remember? I also did on my second one. But after I went once more with the iron and passed it on all the pins again but from inside to outside. I hope you understand what I mean as my English is less than perfect

João

[mbanzi]

Your English is perfectly fine! I believe I did, clearly my drag soldering needs more practice. Probably went too fast or didn't use enough flux. Oh well, with my 3rd transmitter I'll do it perfectly!!!

[jhsa]

He He, I'm sure you will.. I don't know if you read on the er9x128 thread that fortunately when I went with the multimeter looking for shorts between pins, I found with the help of the schematic a shorted capacitor on pin 62, AREF.. it was shorted on it's side by a little bit of chip quick.. If I didn't measure everything I would never have seen it.

João

P.S. - they say on the videos that if you short the first 2 pins with a blob of solder, you will have the right amount to do the drag soldering.. My little experience says, no way. I do prefer to put more solder and lots of flux, even if I short a few pins. I used to get scared of shorting the pins until I found solder wick
Just take the excess solder with it and Bob's your uncle..

João

[tigar]

I got a replacement board coming my my way!
I am wandering what should I do with the fried one?

[rperkins]

save it. ya never know you might need it for a component or 2.