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Okay, before I begin, let me say I already spent hours Googling this and wasting time on certain RC tech websites going through dozens and dozens of pages of unrelated info trying to find specific answers to questions, and still wasn't able to come up with clear answers on what some of the functions do, and how to configure them. I also found some info dated up to a year ago that certain functions may not work properly (or at all), such as the "EXP" (exponential rate) function.

So hopefully this thread and your answers can be a lot more useful to future GT3B owners than "wading through the murk" of RC tech websites. Note that this isn't a hacked system and I'd rather avoid that if possible.

1. I want to decrease my steering servo travel equally in either direction from center. The Optima's steering doesn't require much throw either way, and I find that my servo is pushing/pulling about a quarter-inch farther than it needs to. It would seem that adjusting EPA (End-Point Adjuster) would fix this. I tried decreasing down to 75% but it doesn't seem to reduce the throw. If it's relevant, CH1 has been reversed as per the manual. What is the procedure to adjust the endpoints to decrease the servo travel? All I've found is people saying "Adjust the EPA to change end-points", but not saying exactly how.

2. For an offroad buggy, do you guys recommend using the ABS? Mine is currently set to "OFF". For those who don't know, the ABS function simulates anti-lock braking to reduce skidding by not locking up the wheels when braking.

3. Does EXP (exponential rate) work with current releases of this radio? I've read that with early releases, the EXP doesn't work properly, or at all, without being hacked.

4. What exactly does the DR function (Dual Rate) do?

5. Is it possible to connect an old-style analog servo to the GT3B receiver, such as a Futaba S3003? What happens, has anyone tried?

Thanks for the info!

Wow, nobody??

I figured out how to set the end-points on my own with more trial-and-error. So, in case anyone else happens across this topic and wants to know how to reduce or increase your servo travel, here's what you do (you can increase throw above 100% if you want more travel):

-Go into the E. POINT section for channel 1 (steering);
-Press the big chrome ENTER button;
-Rotate the steering wheel in the direction which you want to adjust; i.e. rotate it all the way to the left. Press the little chrome END button.
-Rotate the ENTER button to the desired percentage; press the ENTER button to save.
-Rotate the steering wheel in the opposite direction, i.e. right. Press the END button.
-Rotate the ENTER button to the desired percentage; press the ENTER button to save.

So basically, you can individually adjust the end-points of either direction of servo throw. On my Turbo Optima, it seemed that 75% in either direction was perfect.

Answers or advice on questions 2 - 5 would still be appreciated.

I have been running an s3003 in my b4 with no problems. No glitches or stuttering.

Kayne wrote:I have been running an s3003 in my b4 with no problems. No glitches or stuttering.

Awesome, thanks for the info--that's what I have in my CYANide car. I'll just swap in the extra receiver I bought with the FlySky. Mounting the steering servos in Optimas is a bit of a PITA and I'd rather not have to do it again.

I will try to answer your questions

Abs does work a bit, I have used it on road but when I'm off road it makes no difference that I could tell

Dual rate I believe is to limit throttle or brake inputs but I haven't actually tried it.

The EXP does work, even stock but if you are going to mod it, don't go past the stock 120% as this seemed to mees up my display a bit.

I modded mine to have +/- 99 steering adjustment which was great.

Sounds like brand radios still have bright days ahead of them

Good luck with the GT3B I have the cheaper GT2B and it works an absolute treat

Paul