RC ground xmitter throttle output versus RC plane xmitter throttle output?

Tom C

Hi all,
I presently only have RC plane transmitters (2.4GHz), but am putting together a Traxxas E-Maxx ground chassis for Robo-Magellan.
The question I have is, can I use a Spektrum plane RC transmitter (2.4GHz) with a Spektrum ground receiver (2.4GHz)?
Is there a way to simulate the RC ground transmitter braking function on the plane RC transmitter? Normally the plane transmitter throttle PWM goes from 1.0ms minimum to 2.0ms maximum throttle. Does the ground transmitter throttle work the same way? Or does it go from 1.5ms to 2.0ms PWM for forward throttle and 1.5ms to 1.0ms PWM for braking with netural at 1.5ms PWM?
Regards,
TCIII

Franklin

You need to check the regulations. With the older frequencies there were frequencies for airplanes and ones for ground vehicles and they were not to be used otherwise. This was for safety reasons mostly but you could get in trouble for ignoring the rules.

Tom C

Hi Franklin,
Thanks for the response, but you missed the point of my post. I am pretty sure that my RC plane transmitter will work with a RC ground receiver because I have several Spektrum BR6000 robot receivers that are essentially ground receivers so that is not the issue. The issue is, what does the throttle output of the RC ground transmitter look like? Is it linear from 1.0ms to 2.0ms like with a RC plane transmitter or does it split the range to allow for the braking function with neutral at 1.5ms? That is the question. I am hoping that I will get an answer here and not have to do it emperically.
Regards,
TCIII

Duane Degn

I have a speed controller I use in an airplane but I believe it was made for RC cars. The reverse starts somewere below 1.5ms but I don't know how far below.

A lot of these type of parameters are programable in the tx unit. I'd image the switch between forward and reverse would depend a lot on the speed controller of the car. Does the car have an equivalent reverse speed range as it does forward speed range?

The speed controller I mentioned only has a single speed reverse so I'd think the pulses to trigger it would be in a narrow range.

Have you checked any of the ground transmitter manuals? I know my aircraft tx manuals have a lot of this sort of information.

ratronic

I consider ~1.1ms to be throttle down and ~ 1.9ms throttle up at least with brushless motors.

Edit: At least that is about what my radio/receiver (Futaba T6J/R2006GS) puts out at full stick range.(a plane/heli radio)

Duane Degn

ratronic wrote: »

full stick range.

I think Tom is after the throttle settings of those car transmitters that use a trigger instead of a stick.

I've seen those car transmitters, but I've never used one.

I think if the trigger is pushed instead of pulled, the car will go into reverse. The question is what is the pulse length of this transition from forward to reverse (if I understand Tom's question correctly).

ratronic

I have a program to read and display up to the first six channels from a receiver plugged into the servoheaders on the PPBD to the Parallax serial terminal showing the microsecond output of each channel. I am not sure whether the ground transmitters output a different throttle range but at least this can tell if there is a difference if you have a ground and a plane transmitter to test with. This program uses P0-P5.

Edit: from looking at a couple of car controller specs it looks like when the trigger or steering wheel is not touched it's supposed to output 1.5ms(nuetral) which is middle throttle stick position on a plane throttle but the aileron, rudder, and elevator sticks/channels output 1.5ms when they are not touched. Perhaps Tom you can use alternate channels for alternate purposes good luck!

Tom C

Hi all,
I want to thank you all for the insights and information concerning my RC ground transmitter signal output issue. Since I do not have an RC ground transmitter I was hoping that a member already knew the answer to my questions. I think that I will use one of my BR6000 receivers with my Traxxas E-Maxx chassis so that I do not have to purchase a RC ground tranmitter and receiver at this point in time.
Regards,
TCIII

Duane Degn

Tom C wrote: »

Since I do not have an RC ground transmitter I was hoping that a member already knew the answer to my questions.

I'm a bit surprised no one here had a ground transmitter.

I looked though one of the manuals on ground transmitters at Horizon Hobby. Several of the graphics gave me the impression that 1.5ms was stop and pulses longer than 1.5ms were forward throttle and shorter pulses reverse throttle.

It looked like the "stop" position was adjustable.

Tom C

Hi Duane,
I concur with your conclusion concerning the neutral position, 1.5ms, and the max forward point being ~2.0ms. While braking is between 1.0ms and neutral. The members over at the Lynmotion Forum came to the same conclusion.

Update: Picked up a new Castel Creations Mamba Monster on eBay and a download of "as received" throttle/brake settings were found to be:
Full Foward: 2.014ms
Neutral: 1.505ms
Full Reverse: 1.012ms

Regards,
TCIII