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Terry

can I hack a FASST TX

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In short I want to hack a T6EX transmitter to mount on a mast. First question is can I connect a buddy lead to it and feed it from the buddy port on my EVO 9 ? The second is will it work as a slave TX ( fed from the buddy port ) with the sticks disconnected ? I want to mount it in a water proof housing.

Thanks, Terry

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You've probably already seen it, but here is what the manual says:

Never connect the T6EX-2.4GHz trainer system with Futaba radios that have the large round "DIN" connector type as it will cause your T6EX-2.4GHz to malfunction. The T6EX-2.4GHz transmitter may be connected to another T6EX-2.4GHz, or any T4EX, T6EXA, T7C, T9C, T12Z, T14MZ, FX-40 series transmitter.

Despite what it says, I suspect it is hackable to a variety of other PPM radios. So roll up your sleeves and get to work. :)

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No I had not seen it, to be honest its an idea that popped into my head while I was driving today and I thought I would float the idea here first.

So there is no 'standard' for buddy ports, thats a shame.

I hoped that I could just make up a buddy lead and squirt the PPM in to the T6EX. Maybe it will be easier to get another FASST TX to use with it.

Terry

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I hoped that I could just make up a buddy lead and squirt the PPM in to the T6EX. Maybe it will be easier to get another FASST TX to use with it.

You should be able to from what is said above.

fig3-03.gif

I presume the warning is valid with the "official" trainer cables which have power connections, and there have indeed been some differences that could be unhealthy.

If you just feed it a PPM stream in the PPM in/GND it should work perfectly well.

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Ahh thats good info Kilrah, I will give it a go.

Thanks, Terry

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I fed a Futaba training port from an external joystick (with a processor of course!) and it worked a treat although I did find that if the pulse widths of the external channels were out of spec (I think less than 1.1mS and more than 1.9mS) the transmitter ignored the external signals and switched off trainer mode.

Peter

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Thats interesting to know, I don't want it turning it self off, thanks.

Terry

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Exact, seen that too. I haven't measured what the actual tolerance was though. Just to clarify it doesn't "turn off", it reverts to its own control, as a failsafe considering the trainer signal is invalid. OK, the effect would be the same to you ;)

Edited by Kilrah

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Just been looking at the Futaba wireless buddy lead (no lead ! ?) .

Can anyone tell me what happens if you walk too far away and the link gets bad?

Dose it warn you?

Dose it just disconnect?

Dose it reconnect when your close enough again?

Thanks, Terry

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The wireless trainer thing is basically a FASST receiver that simply spits out a PPM stream to the trainer port. So I'd assume that if link is lost it stops sending PPM, and the master TX just reverts back to its own control like if the trainer cord was disconnected or the signal became invalid, and uses trainer again once the signal is back.

Just beware it's on 2.4GHz...

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Just returning to this project and found it only has failsafe on the throttle channel which is a surprise to me, cant understand why not on all channels. Has anyone built a solution to this?

I was thinking about a failsafe triggered by the RX data LED.

Terry

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If the Rx data LED does not work out, perhaps you could monitor several servo channels and look for a condition where all have been inactive for several seconds. It's just a PIC and firmware. :)

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Thats an idea but I often fly stait and level for several second with no need of an input when the plane is trimmed well.

Terry

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Futaba has 2 FASST protocol versions, the 7CH one and 14CH one. The 7CH one (used by radios up to the 7C, the models above are switchable between both) indeed only has failsafe on the throttle channel.

The PIC failsafe addon gizmo should recognise the throttle failsafe level or LED status and activate failsafe for the other channels :)

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Just a quick update for anyone that is interested. I built a piggyback board for the RX that monitors the red LED output from the RX. After constant RED for 200 frames it switches the outputs to my preset needs. 1.5ms for the 4 main channels, ch5 is for the camera shutter so no failsafe needed. ch6 brings on the autopilot alt hold and a 7th channel is created by the board which is not controlled by the TX at any time to activate the RTH on the autopilot. I did this the easy way by using 3 smt pics, I could have used just 1 bigger one but this was the easy way as the FASST pulses are a bit odd.

There is no way to adjust the failsafe positions now its built so any tweeking has to be done by adjusting the servo links. Not a problem as I already did it for the autopilot as this needs 1.5ms as its neutral.

In operation when signal is lost it holds the last known servo position for 2sec then switches to the preprogrammed positions.

Terry

post-16-128065561178_thumb.jpg

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OK still trying to squeeze more from the T6EX :)

Dose anyone know if when linked to a buddy lead to supply the frames it can output 6 proportional channels? (if the TX supplying the frame can)

Terry

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