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saabguyspg

Calling all DX7 users......

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OK so here is the thing, I am sure it has been discussed before but many of us have the DX7 and yes it won't assign the right channes to the trainer port.... so...

Has anyone figured out a fix for this? Right now I have my rudder doing the pan and the flaps doing the tilt.... kinda lame and too much to think about.

This is what I was thinking....

The flaps and the AUX switches on the TX are not just on / off switches cause if you hold down the toggle the flaps slowly move up or down.... the same type of switch is on the AUX channel.

Why can we not input some sort of signal onto these switches? Taking the tx apart is a breeze but what sort of signal is required here? The sticks use dash-pots so I assume it is looking for a vairable resistance across the two wires going to the dash-pots.

Why can we not add two plugs (one connected to the flaps and one to the aux) in the back of the TX and apply a signal that the DX7 is looking for, be it a variable voltage or resistance?

I am sure I am talking a little bit out of my A$$ cause my knowlege of electrical stuff is nowhere near the other members here but.... why not ask?

The output from range video's new head tracker goes directly to PPM signal so that is not what we need but I am sure it could be converted to some other value instead of PPM and applied to the "plugs" which would be connected to the pins on the back of the switches.

Anyone? thoughts? am I crazy?

I could just buy the new Futaba 2.4 7ch and use it's trainer port but that is 300$ and I'd rather buy 3 planes.

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Whoa! You're saying that the existing switches aren't really switches but proportional controls? They sure feel like regular switches!

If that's true, they can probably be replaced with dials for manual control.

If you're going the head tracker route, I'm pretty sure I saw somewhere either here or one RCGroups where someone integrated a headtracker right in to the proportional control on their radio.

Please verify that these switches really are proportional. I'll check mine tonight!

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For me it looks more like a software-driven feature, that will "repeat" presses as long as you hold the switch, like a computer keyboard. If it's the case it would be fairly tricky to use as it wouldn't be possible to force a certain position, only incremental changes from the current one... :unsure:

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Yup, kilrah is right... it's like holding down the switch gives a series of pulses as the tx goes "bebebebeep" and the flaps slowly move up or down to the pre-determined max position.

The computer must be looking for a signal each time it receives one... so one beep = one trim movement then it checks to see if the switch had been depressed again.... yes = on more trim movement... the trim moves so slowly you really don't even need head tracking per say but more head up = trim button up head down = trim button down. Then you have to turn off that darn beeping... sheesh I hate that....

I am going to take the tx apart tonight and photograph the switches and wires.

I was envisioning the exaxt same thing... that you could add proportional control to those two channels.

I can see why you can't add proportional control to the gear channel cause it only has two wires but I am pretty sure there are three wires to the flaps switches.

Actually there will be more than that cause it all has to be hooked to that rather large and long switch to activate the flaps independent of the trim "spring toggle" on the right of the flaps toggle.

Definately looking foreward to any other comments.

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Oh yeah, hi Mr. Pibb and Kilrah... thanks for the comments....

btw Mr. Pibb where did you see the head tracker integraged to proportional control ??? I'd love to check that out!

Reason being is that I could sacrifice my rudder proportional channel for the left right head tracking by tapping into the the wires going to the rudder dashpot. Who needs rudder anyway??

Edited by saabguyspg

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Yea, I verified that the switches aren't proportional. I didn't think they were! I didn't realize you were using the trim buttons.

I've wondered if the DX7 can take proportional control through those channels. It probably doesn't, it's probably just expecting on or off from the switches. For the flap swith it's probably just expecting any of the three positions, off, position 1, and position 2. It would be great if it was prewired to handle a pot on those channels.

Honestly, I have no idea where I saw a mod where someone rigged up a head tracker to work in place of a pot in their TX. I tried searching for that a few weeks ago and couldn't find it again. Too much info scattered all over the place!

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For the flap swith it's probably just expecting any of the three positions, off, position 1, and position 2. 

That being said it must be expecting three values not just on and off... ie. position one is "x" voltage or resistance off position is "y" position two is "z" and anywhere inbetween is "x plus .1v" or "x plus .1 ohm" this must be true because one click with the rocker switch and you must get "x plus whatever" to give you a modified position of flaps.

Now that "plus whatever" increment is obviously dictated by the switch and or the computer. We need to measure what happens each time that rocker switch is hit and see what effect it has on the overall positioning parameter be it voltage or resistance.

Honestly, I have no idea where I saw a mod where someone rigged up a head tracker to work in place of a pot in their TX. 

that is unfortunate but not the end of the world.... if we could get  this figured out there are plenty of others that will find a way to make it work.

My latest thoughts were to use a Wii mote linked via a PCTX adapter and use glovepie to emulate the head tracking. This is really quite easy to do buuuut...... this would force you to use a joystick to fly the plane and you have to bring your laptop to the field..... though flying from the warmth of my car while the transmitter sits outside is an appealing idea when it's -25 out like now!!!! If anyone wants me to start a topic on flying from your PC let me know and I will start one.

Ok I did that wrong.... sorry but you get the just if you read the above with my comments in between...

Edited by saabguyspg

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That being said it must be expecting three values not just on and off... 

Nothing special there. A typical setup that would most likely be used there would be 2 digital inputs from the processor connected to 2 (actually independent from each other electrically) push switches under the trim rocker. Each switch has its second pin tied to ground, and the processor lines each have a pull-up resistor, either internal or external. The pins are normally high, and go low when the corresponding switch is depressed. One acts as "+" and the other as "-" in the software.

Honestly, I have no idea where I saw a mod where someone rigged up a head tracker to work in place of a pot in their TX. 

Yeah that's the point, you need to have an analog pot on the TX, which you can remove to connect the tracker. But there's none on the DX7.

Edited by Kilrah

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This just proves what everyone has said but I thought heck.. lets try and fool the computer anyway.

ok so last night i did some digging into the rocker switches etc.

It seems that the computer is looking for either -5 volts 0 volts or +5 volts from the three way posistion switch.

Thinking ok well maybe we will get lucky and with each press of the trim switch the voltage will change slighty.. I pressed the switch..... it stayed at 5 volts

Sooooo I figured that possibly with each press of the rocker trim the computer adds or subtracts a certain voltage (software only).... hoping that if I just changed the voltage manually by applying say 1.2 volts the servo would only move a little.....

Guess what? It moved the whole way over.... grrrrrr... so you can't fool the computer by doing the adding before the signal is sent to the computer from what I can tell. The computer is just looking for a voltage... and it can be anything from 1-5 volts plus or minus.

So from my limited knowledge I think I am at a brick wall. All I was able to do is apply 1.2 volts from a coin cell battery at the right spot and the servo moved as if there were the full 5 volts.

Applying the same 1.2 volts to the dashpots on the sticks makes the servo move just a little bit compared to when you put 5 volts across. So the little coin cell trick works but not for the flaps channel.

The funny thing is that there are the same number of wires to the flaps channel as there are to the proportional channels. (actually plus one cause the gear switch wire is in there too) but they could just re-program the software to look for a proportional channel and you would be set.

Actually I really don't understand why they don't re-program the software to give up flaps gear and aux1 to the trainer and hold the stick control.... we would be set...... it's really just the opposite of what the DX7 already does which is hold all the flaps gear and aux1 channels and gives up the stick control to the trainer.

Oh well... can't say I didn't try!

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It isn't any cheaper than buying a whole new radio, but I had already thrown out an idea here that could/should work and would add the benefit of being able to change out your radio's TX antenna.

Here's the text:

This thread isn't getting as much traffic lately! I thought I'd try to revive it with a question.

Since I'm using a Spektrum DX7 witch isn't apparently compatibile with the TrackR1, I was thinking of an alternative solution that would still allow me to keep my Spektrum and all the receivers I've accumulated and maybe even allow for better performance. Here's my idea, tell me if I'm crazy (ok, that may be true anyway but tell me if this can work )

If I were to purchase a Spektrum module like this or this or this, I was thinking that I could hook a trainer cord up to my DX7, go to the TrackR1, then go from the TrackR1 to the module. Using this setup, I would not only be able to keep my Spektrum gear, but I'd also be able to switch out the antenna to something that may be more fitting for the particular type of FPV flying I was going to do, e.g. higher gain whip antenna for low flying in any direction or patch antenna for long range flying in a particular direction. The module/antenna could also be placed up higher which could help with longer range flights.

Is one module more likely to work or easier to integrate than the others? The JR module is 9 channel, and if I were to purchase the 9 channel receiver with it then I would still have 7 channels to play with otherwise, although I'm not sure I'd need them!

It's somewhat of a pricey solution, but so is everything else in FPV. If you deduct the price of the receiver that comes with it the price isn't really that bad anyway. I won't be able to do this soon...too many other purchases recently , but I am considering adding this solution to my "future purchases" list.

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I love the outside the box thinking here....

So I will try and get this straight.....

You have a track R1 that outputs a PPM signal on two channels

You have the dx7 set to the slave setting where only 4 channels are being output via the trainer jack.

You have a spektrum module that is receiving signals from two sources and outputting the signal through it's own antennae.

Am I correct in this so far?

My questions are:

1) Can you depict which channel the R1 outputs the PPM on? If so then great. If not how do you keep it from ovelapping the stick controls?

2) How do you join the signals together? A simple "Y" cable?

I LOVE this idea. If it costs 239 and comes with a receiver.... that's 189 for the module, I only have to take one TX to the field and don't have to spend 320$ on a 2.4gz FASST 9c Futaba that just does not look quite up to par with the DX7. Plus the Futaba 2.4 receivers are a staggering 100$ each...

I would buy the new AR9000 with the module cause it has a live "dropped frames" and "receiver voltage monitoring" output on it. We could make it so that a tone or beep is produced if frames are being dropped and overlay that on the audio channel... giving us an indication that we are losing frames and it's time to turn back!!!

GIDDEY UP!

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I could be wrong but I think the trainer port outputs all 7 channels.

I've seen mentioned that the head trackers can append a PPM stream, so IF I'm thinking of this correctly:

DX7 sends all 7 channels out through the trainer port TO the head tracker.

The head tracker apends channels 8 and 9 to the PPM stream (or replaces channel 7 and adds channel 8 to the PPM stream).

That signal then goes to the module which thinks it's getting a standard 8 or 9 channel PPM stream.

The questions that need to be answered:

-Does the DX7 output all 7 channels on the trainer port. there's a JR section on RCUniverse where they could probably answer that fairly readily.

-Can the TrackR1 or other head trackers take a PPM signal in and reprocess/append it? I think that's how it is designed, can someone who knows confirm this?

-Can you then easily take the output of the head tracker and input it to the module. Someone who knows more about standard radio modules can probably answer that. I've only had Spektrum radios since I've started, so I don't know much about modules! :D

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From what I know about my dx7 you can either have all controls taken over by the student or just the stick controls. So in this case all controls would be sent over to the spektrum module.

I don't think the tracking devices "accept signals" well at least the latest one form Range Video does not. They just output signals to the Futaba trainer port which then get transmitted to the receiver. Here in lies the problem I think. The futaba transmitter mixes the input from the trainer port with the inputs from the sticks to one ppm stream.... remember this for later

Here is the manual where it states that you can assign the channels that the tracker outputs on for the "Magtrack"

http://rangevideo.com/docs/magtrackr_rev100.pdf

So this signal would have to be overlaid onto the signal from the "student" DX7 on it's way to the spektrum module. I think here in-lies the problem that the ppm streams will be out of sync from eachother.

Sooo unless you are right and the Track R1 has an input... we are hooped unless there is some way of syncronizing the two ppm streams before they are sent to the module.

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OK, I knew I saw it mentioned. If you search the TrackR1 thread on RC groups there are a lot of comments about "PPM Reprocess" mode. I've seen some specific comments about how it adds channels.

http://www.rcgroups.com/forums/showthread....ess#post7036636

I really think this option can work. Unfortunately, my funds are probably a little short right now to make the purchase and try it out. My next purchase will be video goggles. I'd need to purchase the head tracker and Spektrum module at the same time to be able to justify either purchase. I don't think the wife will go for that :rolleyes::D .

Not to mention I'm getting a bunch of stuff delivered today to finish my basement, so a lot of money will be going in to that project...

I'll let you try this out first. :P

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Well now that sounds promising for sure...

here is a link to the Aeropix manual if you have not read it yet.

http://www.aeropix.ch/support/TrackR1_Manual.pdf

in there it states the PPM can be appended though it is not supported in the software as of yet.

Somehow the signal is appended and it says it is "sent back to the transmitter" how does it do this I wonder? Same cable? but the TX trainer port would be sending PPM not receiving??? I am sure it works but I am just trying to wrap my head around it.

In our case the re-mixed PPM would just be sent to the module and it sounds like it would work!!!

Now for the funds... yeah... gonna have to wait on that one too!!

What do you think about the dropped frames signal being sent as a tone over the audio channel idea? Think someone on here can figure that one? Dang that would be really nice to have!

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It depends on the transmitter. On some that would require a hardware mod to connect the tracker output to the RF module after cutting the line from the TX's processor...

Futaba always output the same signal they send to the RF module on the trainer port. But even if there are separate input and output pins, the append/reprocess wouldn't work simply by sending the new signal into the trainer input, as it would lock the controls in place.

The TX takes the stick positions, sends them both to the tracker and the RF. The tracker gets it, appends its data to the signal the TX has just sent, then sends it back to the trainer input. The TX receives it, and transmits it to the RF and the output again. There's where the problem lies, the channels that aren't touched by the tracker will never change anymore. The TX will send what it receives on the input, but as that's what it has just sent it's always the same.

It only works without hardware mod if the TX always sends its own signal before taking the trainer signal into account on the output, not the final processed one. Now I don't know what models do it .

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Kilrah,

I just wanted to make sure you were thinking along the same lines we were about the reprocess/append mode. We aren't talking about using the radios internal RF module. We're talking about using an external module. The signal would never have to go back into the radio.

We're assuming that the trainer port on the DX7 is outputting a PPM stream containing information for all 7 channels on the DX7. That signal would go to the TrackR1 (which I think currently supports reprocess mode according to some comments on RCGroups). Then, the signal would go from the TrackR1 to an EXTERNAL Spektrum module, not back to the DX7. From your response it sounded to me like you were thinking that we meant that the signal was going back into the radio and to the RF module inside the radio. From what I understand, the DX7's don't work that way anyway. Internally they never even use PPM.

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I think you are right the DX7 apparently does not use PPM internally... so they claim it is faster because of it.

Mr. Pibb that's how I was envisioning it too... I am wondering how to get the stream to output on a different cable... if it presently outputs "back" on the same cable we may need to do some hardware mods..... Like you said we need it to output separately to a external module.

I have purchased a PCTX module for my DX7. I am going to attempt to use a Wiimote for the head tracking and a joystick to fly the plane.... I don't mind bringing my very small laptop to the field. This all hinges on the fact that hopefully if I give a proportional signal on say channel 5,6, or 7 through the trainer plug that the transmitter will transmit a porportional signal to the receiver..... I know Enduance RC has a program that would save me loads of time but I can't fly for months anyway so I am going to try and make my own program.

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Very cool!!!!

I am in the same financial situation as you..... christmas, etc etc.

On a different note the Endurance R/C module does allow the use of all channels as proportional channels with my DX7 (finally got around to trying it)

Now for me to learn how to program in c# cause I can't afford the Servo Commander software.

Glove Pie may help me out a fair bit here too.

Anyway good luck and keep me posted!

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Just an update:

I'm going for it! I'm going to purchase the Spektrum module and the TrackR1 after Christmas. Let's hope that we'll know if it works by the end of January. :)

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Just following along with you guys since I have a DX7 so keep us up-dated. I did however pick up a Spektrum module for my 9C so I can use it with all my Spekrum RX but I still would like to have a Head-Tracker mod for the DX7 :) .

Edited by Crash9

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Just following along with you guys since I have a DX7 so keep us up-dated. I did however pick up a Spektrum module for my 9C so I can use it with all my Spekrum RX but I still would like to have a Head-Tracker mod for the DX7 :) .

I'm trying to decide if I'm going to order a TrackR1 in the next week when it's in stock or if I should wait for the TrackR2 which is supposed to be the same price and will come out around the end of the month according to Anthony. The TrackR2 is supposed to have built in drift correction that helps it to self re-center (assuming you are looking forward most of the time anyway...)

I'm going to order the Spektrum module soon. I was going to order it today from Toddsmodels for $250, but I'm thinking that I might wait since I really can't do much with it until I have the head tracker. I'm just anxious to get everything together... :D

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Waiting a little while is always worth it!! drift correciton is worth the wait for sure..

For now I am going to mix my pan servo with my ailerons and add some exo to it so when I bank the pan servo turns.

good luck and keep us posted!

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I'm going to order the Spektrum module soon. I was going to order it today from Toddsmodels for $250, but I'm thinking that I might wait since I really can't do much with it until I have the head tracker. I'm just anxious to get everything together... :D

Mr Pibb, I've been lurking around here for a few months just learning. I can't help think it might be simpler to use a second radio. Toddsmodels is advertising the nearly released DX6i for $180 USD - couldn't you run the headtracker through one of those, with an additional Rx onboard? Still cheaper than the module, and you get a second functional radio set in the deal. I am assuming of course that having two Spektrums running nearby will work ok, but isn't that exactly what Spektrum is meant to be good at? This way you also get to keep the supposed native DX7 DSM2 responsiveness, instead of introducing the lags of DX7 to PPM, followed by PPM to DSM2 conversions. I guess dragging two Tx around isn't all that elegant, but then it sounds like you will have a fair collection of cables and boxes and tripods as it is. What do you think?

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