https://docs.google.com/document/d/1...it?usp=sharing

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Simple and Easy Wireless Student-Trainer Setup for Futaba Radios

I never trained another to fly an RC model. This because I never learned in an orderly manner myself and because I never trusted myself to explain well. Thus, I never bothered with getting a student-trainer setup.

One day, however, a friend asked to have a “go” with one of my models - a very nice flying wing. So we did the “bear-hug-dance-around-the-radio” - me holding the radio and him controlling the model while, so to speak, embracing me. With our height differences - it was not comfortable nor entirely safe.

Thus deterred from further exploits of this nature, I decided to get a student-trainer setup.

My then-radio was a Futaba 9CH with a TM8 module. My spare radio was a Futaba 8UA, 72MHz. Aha! All I needed was a DIN to Futaba Micro trainer cable - easy enough. But a trainer CABLE! 2013! Come on! Also, the 8UA was a dead end. After all, it would be replaced or traded away and I would probably get a modern Futaba radio instead, making the 9CH my backup.

I decided to experiment. The Futaba Micro connector (pinout here). So there is PPM out/in on the port. What if….

In perusing various after-market 2.4GHz receivers, I remembered noticing that FrSky had something resembling PPM out. Searched and found - the TFR4-B had the functionality. Not that it helped yet - the 8UA was a 72MHz, but it was modular. And my TM-8 was already in use. Maybe other module/receiver combos from FrSky had that functionality. And - so they did - the D4R-II also supported CPPM.

So - I wagered a bit of money and ordered one D4R-II, the DF 2.4GHz combo, and - lucky I noticed - 6pin Trainer Port Plug. Lucky, indeed.

Once they arrived, some three weeks later, I tested the setup and… it worked. Right off!

Here’s what needs doing:

Bind the D4R-II Rx to the DF module
Short the SIGNAL pins on channels 3 and 4 on the D4R-II
Plug the trainer port plug connector into channel 1 on D4R-II
Plug the other end into the trainer port on your Futaba Tx
The D4R becomes the student Rx
Enable trainer on the model you want to test/use/train on
And...
The student’s Tx transmits to the student Rx
The student’s Rx signals the trainer’s Tx via PPM in
The trainer’s Tx transmits to the primary Rx on the RC model
Voill! It works!

To make things clean and tidy, I stuck a bit of male velcro to the back of my 9CH, stripped the D4R-II, shrink-wrapped it and velcroed it to the Tx. The antennae I hid in two tubes that are stuck directly to the shrink-wrapped Rx.

The spare Rx I was left with - the D8R from the combo - I swapped with a friend for… ummm… I am not sure what. May be a couple of beers.

Best of all - this will work with ANY transmitter can bind a FASST (TF4R and TF4R-B, the student Tx must be a FASST system) or an ACCST (D4R-II) Rx. I have tested the very same setup on friends’ Futaba 12FG, 8FG, 14SG and as soon as a Taranis radio arrives here - on that as well. And my 8UA? I still have it. It works. It is a nice radio. No need to replace.


The D4R-II

DF Module Combo


The 6-pin trainer cable

TF4R-B

PS - I am _not_ associated with Hobby King, Futaba or FrSky. I am a customer and user of all of their products. This works for me - but test everything yourself.