FS-GT3C using channel 3 for transmission servo

[Westside Charlie]

I'm building a new Vaterra Ascender and want to put in a 2-speed transmission. I've ordered the transmission parts but am puzzled about how to get my FS-GT3C set up to let me use channel 3 for the transmission servo.

I've been down the rabbit hole on various forums about the transmitter, which sounds cool, but am hoping is totally unnecessary for what I want to do--switch the micro servo between two speeds.

Shouldn't I be able to set this up with the stock transmitter?

Any ideas are most welcome.

WestsideCharlie

[heyok]

Whenever I have a GT3C or GT3B in my hands, the first thing I do is upgrade the firmware so I'm not exactly sure how it works on a stock one.
I can tell you what you need to do though.
The big deal with running the transmission shifter is that you carefully set the servo end points. If the servo tries to drive the linkage too far, the servo will most likely fail quickly. It will also use up more power than it should.
Before you tie the servo to the shift linkage, play with the transmitter and see how adjusting the end points will limit how far the servo horn will move when you select its two positions.
Probably the best way to do this is set the travel to minimum, connect the linkage then extend the travel until it is just enough.

Hope that makes sense. It did in my head as I typed this out.

[Westside Charlie]

heyok, what you wrote makes perfect sense. My problem is more fundamental, though, since I don't get any response at all when I click the channel 3 button. I tested the micro server in channel 2, so I know it works, but when I plug it into channel 3, -- nothing. I'm pretty sure I'm doing something dumb (or not doing something.) I should get a response, shouldn't I, just by plugging in and then clicking the channel 3 button? Channels one and two are working fine.

Let me know what you think.

Thanks!

[Ditchrat]

Originally Posted by Westside Charlie

heyok, what you wrote makes perfect sense. My problem is more fundamental, though, since I don't get any response at all when I click the channel 3 button. I tested the micro server in channel 2, so I know it works, but when I plug it into channel 3, -- nothing. I'm pretty sure I'm doing something dumb (or not doing something.) I should get a response, shouldn't I, just by plugging in and then clicking the channel 3 button? Channels one and two are working fine.

Let me know what you think.

Thanks!

Channel 3 is a simple on/off. Take a look at this video, it shows some features of that channel. I don't think what the guy(in the video) is doing will work for you, but watching it gave me an understanding of things that I could do/not do on channel 3.
https://www.youtube.com/watch?v=4sbQF3BAC-Q

[heyok]

Like Ditchrat was saying, it is a two position (on/off) channel.
Are you using the push button on the handle to operate the channel, or using the trim switch (three position slide switch)?

[Westside Charlie]

Well, I've tried pressing the button and using the trim switch and get no response. It would be great if the trim switch worked, since I think I can achieve what I want with a 3-way switch.

I'll try plugging in a light set just to confirm that I actually am getting signal from channel 3. I assume that if it's working then the lights would simply turn on and off. If that works, then there is something else awry.

But from the various response I've been getting, it sounds like I should be getting some reaction in the servo, right?

[heyok]

Yes, the servo should move unless both the end points are set the same.
If you plug a light into CH3, it will just light up unless you are using some kind of light controller.

[Westside Charlie]

OK, I'll check my end points tonight and hope that'll do it.

Thanks!

[losikid]

Are you sure it wasn't programmed with the new firmware?

Press and hold enter after power up. If something like "061" shows up on the screen you have the new firmware and I believe in 0.6.1 ch3 is defaulted to off instead of stock control. This is because a lot of people were plugging in their winches and blowing them up.

[Westside Charlie]

Oh, I'll check to see if that new firmware is loaded.

Thanks!

[Westside Charlie]

I checked to see if version 6.x is installed, and it's not, as far as I can tell. I also set one of the endpoints for channel 3 so it's different from the other point. There is still no action from the servo from channel 3. I'm still convinced it's a set-up problem but I'm not sure what it is. I'll keep looking...

[Westside Charlie]

A quick update - Channel 3 is now working and successfully drives the servo to shift gears in the Twin Hammers transmission.

I thought the problem was a set up issue on the transmitter, but first, I decided to test channel 3 on the receiver, and accidentally shorted channel 2 in the process. (Idiot!)

So, I ordered a new receiver ($10) and did the rebinding, and bam! - channel 3 now worked!

I'm now thinking that the problem all along had been some issue with binding, and if I had re-bound (re-binded?) in the first place I could have solved the problem.

Now all I have to do is finish my build and start crawling!

Thanks Everyone!

[losikid]

Originally Posted by Westside Charlie

A quick update - Channel 3 is now working and successfully drives the servo to shift gears in the Twin Hammers transmission.

I thought the problem was a set up issue on the transmitter, but first, I decided to test channel 3 on the receiver, and accidentally shorted channel 2 in the process. (Idiot!)

So, I ordered a new receiver ($10) and did the rebinding, and bam! - channel 3 now worked!

I'm now thinking that the problem all along had been some issue with binding, and if I had re-bound (re-binded?) in the first place I could have solved the problem.

Now all I have to do is finish my build and start crawling!

Thanks Everyone!

It was probably the rx.