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Futaba SBus to PPM converter

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Hi all, I'm looking for a Futaba SBus to PPM converter.

Does anybody know of such a thing with a proven working track record or would anybody be interested in building such a thing? (Hint to Thomas)

I'm sure it would be a great seller.

SBus protocol

I can't vouch for the accuracy or completeness.


There is also this but it is sold as a pcb only and I dont have the knowledge to program it, ( I could build it), I could not find any reports attesting to reliability, some negative actually.


I would like to feed PPM into an OSD that has newly developed firmware to support PPM in while still having ordinary servo connectivity to the receiver for things such as Head Tracking, flaps etc

I've considered a PWM to PPM encoder but it would add wiring complexity as I still want access to the receiver outputs for the above mentioned things such as Head Tracking and Flaps etc.

If eventually I need to use a PWM to PPM encoder I will stick with my Futaba R6014HS, If I find a proven (or one is built) SBus to PPM converter, I will be using a R6108SB receiver


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I've never even touched a Futaba SBus system so it is all a mystery to me. But maybe the best solution would be to add the SBus decoding into the OSD. I found a discussion where a MK user added it to his flight controller. Maybe you should sweet talk the OSD maker into adding something similar.

Here's the MK SBus code:


Here's the discussion:


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Thanks for your replies guys, the OSD's makers name is Bill (no more clues will be given). I will try to sweet talk him and in the mean time I might try to build the project above.

I looked at the FrSky receivers as linked by Kilrah but they are limited to 10 channels and I would like to make full use off my 12 available channels with my existing system.


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  • 5 months later...

hello all forum rc agradesso to be part of this forum

I use ese receptor changed in a simulated funsiona pefeito wireless so I entedir the bus fuciona s the same way and that

Step by Step Walkthrough

Please read the whole process before start! To exclude the possibity that your receiver is dead on arrival (DOA), you should first connect a regular RC servo and power supply to check that it is working correctly.

Step 1: Open the case


The case consists of a bottom and top part. They are connected by four notches snapping into the corresponding cutouts on the lower case. Take care of electrostatic discharge (ESD) risks by tapping a radiator or other metallic grounded object (personal computers are grounded) before opening the case. Best practice is to use an ESD arm strap, if available.

Push the notches back with a small screw driver (blade width of 2.5 mm fits perfectly) and at the same time gently apply pressure to move the two parts away from each other.

Watch out to not pull on the antenna wires, you can remove the rubber tubes holding them to the plastic case.

Step 2: Remove Resistor connecting Plug


Depending if all seven channels should still be usable, two options exist: You can connect the sum signal to an additional header, which you should fix tightly, e.g. by hot glue, or you disconnect the servo signal on one channel and connect the sum signal to this header.

This tutorial will proceed by disconnecting channel 7, as this channel is not usable with the six channel T6EX transmitter. Desolder now the resistor in front of the header for channel 7. In theory you can undo the modification by removing the cable (later step) and re-adding this resistor. The receiver is build in a lead-free ROHS process. The melting temperature is therefore higher than with usual solder. We had to ramp up the soldering iron to 370° C (700°F) to melt the solder. Apply heat to both sides of the resistor until you can gently slide it off its position.

Step 3: Connect PPM Sum Signal


This step connects the sum signal to the freed header. You need a very tiny cable. Remove the insulation by 0.5 - 0.8 mm (0.3”). Apply solder flux to both ends and cover them with plenty of solder. Place one end on one of the two marked pins (it is easier on the left IC, as you have additional space on the edge) and solder it to the pin. Make sure that is is connected right by gently pulling on the cable. Place the other end on the signal pin (see photo) on the header and solder it.

Step 4: Check

Check for remaining solder on the PCB or bridged pins. It might be a good idea to secure the sum signal cable against vibrations by hot glue or epoxy. If you have an oscilloscope at hand, you should get five signals of about 1 ms, 20 ms break and the same again. The PCB should now look like the photo.


Step 5: Close the case

You can easily add the case by placing the pcb inside and snapping the notches back into the bottom part. Your receiver now looks exactly the same. It might be a good idea to mark port 7 as sum-signal out.

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sou brasileiro fanatico por heli modelismo sou navato na aria de helimodelismo tenho poco conhecimento na aria de eletronica essa ateração do receptor r 617fs acima postada por mim me gero uam duvida sera que ar posabilidade de funciona o esquema dessa alteração para o treinir sei fio se tiver auguei que possa avaliar as diferencia entre o WTR-7 FASST e essa alteração o problema e que um e in entrada ppm e o otro e out saida ppm por vafavor essa possabida de usa essi sistema comu treini sem fio tenho gande sartifação de fazer pate deste forum obrigado a todos que compatilha estas maravilha da eletronica com nosco valeu todos??????

'm Brazilian fanatico by heli modeling navato am in aria of helimodelismo poco have knowledge in this aria of electronic ateração receiver r 617fs above posted by me me gero uam doubt that air will be posabilidade works of this scheme amendment for the wire if you know treinir auguei that can evaluate the difference between the WTR-7 FASST and this change the problem and that an entry ppm and in and out of each other and the ppm output for this vafavor possabida of essi system uses wireless commu treini have gande sartifação making pate this forum thanks to everyone who compatilha these electronic marvel with Nosco earned all???

Edited by rejaorac
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  • 7 years later...

Hey all, I am new to the race drone hobby and have a r9ds radiolink receiver I'm trying to connect to an Immersion Vortex 285. I have a CPPM to S-bus converter cable on the way... Does this sound accurate? I can't find a video or explanation anywhere. Manual just says you need an Immersion "optional" cable but can't find that anywhere... thank you

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I have a CPPM to S-bus converter cable on the way... Does this sound accurate?

The Vortex's R/C receiver port expects PPM (CPPM). I believe that some Radiolink Rx's have a "PPM" output, so try to use it if yours is equipped with this. But if your R/C Rx only has S.Bus then the special protocol convertor cable can be used to convert S.Bus to the PPM signal required by the Vortex.

FWIW, I don't own a Vortex 285 or Radiolink. So check with the user manuals if you need more thorough advice.


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  • 8 months later...

Hi....Wire a Futaba sBus signal through it and you can peruse it in a TTL level UART at 100K baud. I have a board arrangement to peruse in sBus from 4 gadgets and mux a yield to 3 different gadgets on a UAV at work. I can get (12) 11bit channels and two 1bit channels from my 8FG and the equivalent from a 12Z. The signs are without jitter, much cleaner than perusing PPM or individual PWM's.

pcb assembly online quote

Edited by KattiMini
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