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Is that "SWITCH ERROR" all in little caps letters and alone on the screen? If yes it sounds like you are still running the stock firmware, which can not support telemetry.
If you want telemtry it is necessary to reflash the radio with openTx or ER9X, with frsky option.

Can I plug in an Orange TX module if I have modded my Transmitter like this?

NI0X wrote:Can I plug in an Orange TX module if I have modded my Transmitter like this?

I have not had any problems with it.

Nice to read it that way

I did this mod and all I got is "No Data". Please help me figure this out.

Need more details. Any pictures? Any shortcuts? What did you do exactly?

More details: Resistors used are standard 1/8W 47 ohms and 1k ohms.
Receiver is X8R in D8 mode.
Module is DJT.
On the RX trace I cut to place an SMD resistor and then found that Radioshack didn't have any so I bridged the cut with a regular resistor as you can see in the picture.
All cut traces have been tested with a multimeter.
Thanks for the help. This is rather annoying.

Hmm isn't a cut missing there?
Also, are the mainboard mods really correct? Doesn't look like the first resistor on the row is disconnected form the CPU pin, or is it?

Kilrah wrote:Hmm isn't a cut missing there?

Nqr2AAA.png

I did the cut but bridged it with that standard 1k resistor you see in the picture. You bridged your cut with an smd resistor so as far as I can tell there is no actual "cut" because it is bridged.

Kilrah wrote: Also, are the mainboard mods really correct? Doesn't look like the first resistor on the row is disconnected form the CPU pin, or is it?

Yes one resistor is still there. So for the rerouting of the switches I have one 200 ohms smd resistor (measured it) and for the other wire a standard 220 ohms resistor. Both switches work now but even if they didn't that wouldn't effect RSSI right?

popwebz wrote: I did the cut but bridged it with that standard 1k resistor you see in the picture. You bridged your cut with an smd resistor so as far as I can tell there is no actual "cut" because it is bridged.

There is a cut, and each side of the cut is connected to one side of the resistor. So there is a 1k resistance instead of the direct contact. From what I see you did the cut but then bridged it again with a direct connection using the leg. That's no good, if you have no resistor you should rather leave it open.

Kilrah wrote:Both switches work now but even if they didn't that wouldn't effect RSSI right?

No, but you need to make sure the switch is not connected to the CPU pin anymore. With one of them it's easy to see it's disconnected as the SMD resistor is gone. But from what the photo shows the other resistor is still in place, so unless you've cut the trace further (can't see it, it's below the wires) the switch still conflicts with the telemetry signal.

Kilrah wrote:

popwebz wrote: I did the cut but bridged it with that standard 1k resistor you see in the picture. You bridged your cut with an smd resistor so as far as I can tell there is no actual "cut" because it is bridged.

There is a cut, and each side of the cut is connected to one side of the resistor. So there is a 1k resistance instead of the direct contact. From what I see you did the cut but then bridged it again with a direct connection using the leg. That's no good, if you have no resistor you should rather leave it open.

Kilrah wrote:Both switches work now but even if they didn't that wouldn't effect RSSI right?

No, but you need to make sure the switch is not connected to the CPU pin anymore. With one of them it's easy to see it's disconnected as the SMD resistor is gone. But from what the photo shows the other resistor is still in place, so unless you've cut the trace further (can't see it, it's below the wires) the switch still conflicts with the telemetry signal.

The trace to the CPU is cut for that switch even though you cannot see it. It is very tight there but the cut is deep and I've checked it.

I still don't understand the difference though or why it is not good. Is it because the current chooses the path of least resistance and so skips the resistor and instead goes through the trace? As far as I can see that trace doesn't lead to anything.

If attaching the leg of the resistor to the trace will not work what is the procedure to use a regular resistor?

popwebz wrote: I still don't understand the difference though or why it is not good. Is it because the current chooses the path of least resistance and so skips the resistor and instead goes through the trace? As far as I can see that trace doesn't lead to anything.

If attaching the leg of the resistor to the trace will not work what is the procedure to use a regular resistor?

The via simply needs to be disconnected form the rest of the trace.
What I see on your picture is that you (likely) made the cut, but that you then bridged it by soldering the same leg of the resistor that goes to the module connector to both sides of the cut. Maybe the photo is bad and there's something I don't see.

Yes it is bridged in the module! The cuts are not bridged in the radio. That said how do I procede? Do I make a new cut after the resistor's leg? Please explain.

You connect the leg only to the track, not to the via side of the cut. Leave the cut open. Note that this is a bit risky, it's easy to rip the track off with a rigid leg if you apply any effort to it. That's why I used flexible wire.

Yeah the track already lifted once. What do you mean the "via side of the cut"? Guess I don't know the difference between a via and a track.

Is there a significance to where you placed the cut?

The via is the little hole that goes through the PCB.
The first pic in the first post of the thread shows the cut. You've got the blue wire, the via on the right, and the cut inbetween. The 2nd pic shows the cut was then bridged with the 1k resistor.
And no, no significance where it is, as long as you connect your wire on the "track" side of the cut.

It seems I understood this until you mentioned the bridged 1k resistor. So your circuit looks like this:
VIA - resistor < track and wire

If I were to connect the leg of my resistor to only the track side of the cut the circuit would be open and would look like this:
VIA - break < resistor - track

So if I were to do what you just suggested (connect to track side only) the Via would not be in the circuit yet it is in your circuit. That is what is confusing me now. Do you understand what I am saying?

Just look at the first picture of the thread and do it like this.
The small SMD resistor is not important, as explained in the text it's only there to allow reflashing the FrSky module. You don't need that, so just leave it out if you don't have one.

What's needed is the (bigger on my pics) resistor that goes between the track and module connector.

OK so to clarify I need to:
1. Desolder the 1k ohm resistor I have there and make sure the cut is not bridged.
2. Replace the 1k ohm resistor with a 47 ohm resistor and solder it farther down the track so the via is not at all connected to anything

When I read your first post it seems you said the opposite (that the 1k was needed and the 47 ohm was "only for protection") so to clarify I DO need to use a 47 ohm resistor?

popwebz wrote:OK so to clarify I need to:
1. Desolder the 1k ohm resistor I have there and make sure the cut is not bridged.
2. Replace the 1k ohm resistor with a 47 ohm resistor and solder it farther down the track so the via is not at all connected to anything

Yes.

You are a genius it works! Now, do you know how to calibrate telemetry values from my X8R in OpenTx?

So I followed these steps CAREFULLY and even did them all 3 different times and keep getting the same results

I've searched DIYDrones, OPENRC forums, RCGROUPS forums, HobbyKing forums, and Google. I fee like I'm the first one with this problem.

I think I might have fried my AtMega64 but I'm not sure. When I turn it on it works great for about 3 minutes then the screen starts getting all pixelated and distorted, finally it freezes. When I restart it, it just gets worse and worse. Here is a video of it: https://www.youtube.com/watch?v=A5Sg2P8gTgo . I know it has nothing to do with the FrSky module or the smaller board which is on the back of the transmitter because I've used my Arduino to power up the Tx and it still gives me the same results. The problem has to reside in the mainboard. I even tried bypassing the trace cuts I made by running a wire directly from the AtMega's pins to the resistors (to bypass the trace cuts). I've ran out of ideas and I'm so frustrated :/. Has anyone seen this happen before?

Blue wire is (RX)wire goes to 5th pin in module, now in radio on 5th pin is the red one and tis the same (RX)wire.
So why red wire is soldered to(TX)pin on radios pcb?

Serial links are crossed. A device transmits (TX) into the other device's receive (RX) port.

Hi everybody,

I would like to make the Mod in order to get the telemetry on my Turnigy 9x screen, using an FrSky DJT module. I think I understand what needs to be done but I have two questions.
a) I would like to preserve compatibility with my Turnigy stock module as I have a couple of models, all with a Turnigy receiver, and I do not want to change them all. So, once the mod is executed and the FrSky compatible firmware loaded, can I still use my stock module ? Should I modify it ? Do I have to reflash back to er9x ?
b) Which one is the correct firmware for FrSky at this time ?

Thank you !

a) Yes the stock module still works.
b) For er9x, you flash er9x-frsky.hex.

I would recommend doing the mod that does use the the RS232 level converter. This provides an inverting operation on the signals. In my opinion, the mod needed to the DJT is easier to do. Also, with the inverting operation available the FrSky XJT module plugs in WITHOUT and modification needed to it. er9x-frsky also supports the XJT module.

Mike.

I also prefer the mod with the level converter. I don't like to mess with the RF module..
I do have a DJT, but the other radios have the DHT that is installed inside the radio, with the antenna at the top, and it doesn't need any modification whatsoever. As a RS232 level converter I used the frsky upgrade lite..

Please have a look here:

http://openrcforums.com/wiki/index.php/ ... y#Overview

João

can anyone confirm will any of these mods allow a bluetooth adaptor to be connected to the tx rx and send telemetry data to android via multiwii ex-gui ?

Firstly sorry for a shameless bump on a particularly old thread but i have not found an answer after scouring google for what seems like an age and it didn't seem appropriate to start a new thread about this module.

I have a DJT module with this modification without the level converter in my 9x modded to receive the FrSky telemetry on screen which works perfectly. Ive just purchased the Taranis which now has this ridiculous EU LBT restriction on it so the internal XJT will not communicate with my older D or V series receivers. Is it possible to use the external DJT module in the Taranis so I don't need to upgrade all my receivers straight away?

Also if the module is safe to use is it also possible to display the D series telemetry on the Taranis also. This does lead me on to another semi related question, when setting the Taranis up in Companion 2.2 i dont have the option to select the D series telemetry. On the telemetry screen there is only the S.Port option and the drop down box is greyed out.

Thanks for any advice.