GT3B Hack Question and Answer Thread

[truebrit]

I am looking to buy the STM8S-DISCOVERY board on ebay, some say with debugger and some say with st-link, is that the same thing, does it matter?

Also on the overkillrc pdf there is no mention of modding the stm8s board, but all the video tutorials show either cutting the board or de soldering the sb1 and sb2 points and the overkillrc instructions show a 4 wire connector whereas the videos show 3 wires, is this the reason for not modding the stm8s board?

Thanks.

[holycaveman]

I have a question before I buy one.

I DONT want 4ws or crab walk.

I WANT completely seperate control of the rear steer at the same time as the front. Like another steering wheel for instance.

Thanks

[JokersWild]

Won't be an actual steering wheel but you can control independantly on a % step rate. That's how I have mine and I like it a lot.

[holycaveman]

Thanks. That will work!

[JokersWild]

No problemo..... I have mine set on d/r switch........ At a 20% rate each way. I think its about 5 positions each way. Then to center push straight in for a second and auto centers. You can add more steps but I have found 20% is great on my c3 rig and I drive the hell outta it.

[DrDiff952]

When I got mine from Overkill RC it was ready to go. No mods necessary

Advantage Overkill RC!

Originally Posted by truebrit

I am looking to buy the STM8S-DISCOVERY board on ebay, some say with debugger and some say with st-link, is that the same thing, does it matter?

Also on the overkillrc pdf there is no mention of modding the stm8s board, but all the video tutorials show either cutting the board or de soldering the sb1 and sb2 points and the overkillrc instructions show a 4 wire connector whereas the videos show 3 wires, is this the reason for not modding the stm8s board?

Thanks.

[truebrit]

Originally Posted by DrDiff952

When I got mine from Overkill RC it was ready to go. No mods necessary

Advantage Overkill RC!

Not much use to me mate, unless I go back in time and un-buy the TX.

[losikid]

Originally Posted by truebrit

Not much use to me mate, unless I go back in time and un-buy the TX.

Um...

GT3B Firmware Flashing Kit

[truebrit]

Originally Posted by losikid

Um...

GT3B Firmware Flashing Kit

Yes mate I saw that, but I all I need is the board, I'm in UK so much easier to get it here.

So all I need to know is... I am looking to buy the STM8S-DISCOVERY board on ebay, but some say with debugger and some say with st-link, is that the same thing, does it matter?

Also on the overkillrc pdf there is no mention of modding the stm8s board, but all the video tutorials show either cutting the board or de soldering the sb1 and sb2 points and the overkillrc instructions show a 4 wire connector whereas the videos show 3 wires, is this the reason for not modding the stm8s board?

Thanks.

[JokersWild]

Originally Posted by truebrit

Yes mate I saw that, but I all I need is the board, I'm in UK so much easier to get it here.

So all I need to know is... I am looking to buy the STM8S-DISCOVERY board on ebay, but some say with debugger and some say with st-link, is that the same thing, does it matter?

Also on the overkillrc pdf there is no mention of modding the stm8s board, but all the video tutorials show either cutting the board or de soldering the sb1 and sb2 points and the overkillrc instructions show a 4 wire connector whereas the videos show 3 wires, is this the reason for not modding the stm8s board?

Thanks.

St link........
Either break board or desolder sb1 and sb2......

4 wire connector needed

This is why he sells it ready to go......

[ST3 Rock]

Well I just finished reading every page of this thread. I got my GT3C. I just received the firmware kit from Overkillrc.com So I'm going to attempt this weekend.

I want to thank everyone on this forum for all of the excellent dialogue centered around doing this hack.

Losikid has done a excellent customer service job providing detailed information and help.

Just about every question I had was answered by reading this thread.

I highly recommend doing that prior to starting the upgrade.

[Irwin Fletcher]

Look forward to hearing how it goes for you. I was going to attempt it myself but instead am waiting for more stock to become available. Work and Family sucks up more time than I have to try and do this. Plus I am in the process of converting a Futaba 6EXA over to GHz as well. Had to prioritize my work a bit.
I agree Losikid has laid everything on the upgrades out well. Hope everything goes smooth for you

[jopes]

Just installed the parts on my GT3C and flashed it with the newest firmware.

I have the 3rd channel working on the ch3 trim. It works, but I can't figure out how to set the trim and end points on it. It is maxing my steering out and when in the center position it is like 30 degrees. At first I thought I needed to adjust the servo horn but when I steer left it is full steering.

[JokersWild]

Originally Posted by jopes

Just installed the parts on my GT3C and flashed it with the newest firmware.

I have the 3rd channel working on the ch3 trim. It works, but I can't figure out how to set the trim and end points on it. It is maxing my steering out and when in the center position it is like 30 degrees. At first I thought I needed to adjust the servo horn but when I steer left it is full steering.

It's in the sub menu...... Not at my controller right now.

[JokersWild]

Originally Posted by Irwin Fletcher

Look forward to hearing how it goes for you. I was going to attempt it myself but instead am waiting for more stock to become available. Work and Family sucks up more time than I have to try and do this. Plus I am in the process of converting a Futaba 6EXA over to GHz as well. Had to prioritize my work a bit.
I agree Losikid has laid everything on the upgrades out well. Hope everything goes smooth for you

Converting the 6exa..... Depending what you like and what you are using it for you may not like the delay through the module

[holycaveman]

Losi kid I got $ waiting for them to be back in stock! Yes I saw your post.

Thanks.

[jopes]

Originally Posted by JokersWild

It's in the sub menu...... Not at my controller right now.

I didn't see it in the sub menu, unless I am not going to the right place.

[Irwin Fletcher]

I have green cash money burning a hole in my pocket to get a GT3C controller when they are ready. Can't wait!!

[losikid]

Originally Posted by holycaveman

Losi kid I got $ waiting for them to be back in stock! Yes I saw your post.

Thanks.

Originally Posted by Irwin Fletcher

I have green cash money burning a hole in my pocket to get a GT3C controller when they are ready. Can't wait!!

I've had a nasty cold for a week or so now. Once it goes away I'll get radios modded and posted to the website (this weekend?).

I don't think I should be getting cold germs all over the radios

Originally Posted by jopes

I didn't see it in the sub menu, unless I am not going to the right place.

Trim:
Scroll to trim, press and hold enter, choose channel, press enter, adjust to your hearts desire...

EPA:
Scroll to E.Point, press enter, choose channel, press enter, use the steering wheel to select between left and right e.points. Adjust them with the scroll wheel to your hearts desire...

Although, your servo horn and/or steering linkage is most definitely off if your off center by 30 degrees. The channel is CENTERED when the channel is at "0" on the radio. So your servo will be CENTERED when the the radio is at "0", so if your end result is not centered like it's supposed to be, check your servo horn and servo linkages.

Trim is for making small adjustments that is hard to correct mechanically.

[ipattie]

First, thanks for all the cool tech info here, thought I'd add back, hope not a duplicate.

I got the Turnigy GTX3 (Flysky GT2B clone) and the expo works fine, and while I will replace the VR as per in this thread, but may not reflash, I first tried to used a $5 DC-DC step up converter regulator to run a 2S1P LiFe RX pack in the transmitter, and it works great! Thought was to use only a 2S LiFe which is plenty, but avoid the low voltage alarm at 9v because I'm not ready to reflash yet.

I took out the 8 cell AA holder, and there is plenty of room for the DC-DC converter and a 1450 Mah LiFe battery. I set the regulator output to 9.2V, which it holds steady as the battery goes down (but LiFe have a pretty flat curve anyway), and I think the low voltage prevents the stock VR from overheating or being too inefficient. Regulator handles input from 3V to 34V and up to 2.5 amps. The GTX3 amp draw is below 0.2 amps.

I.e., light long lasting battery, charge same as the LiFe 6.6V used in your car. I've had everything turned on for 4 hours, and LiFe voltage has dropped from 6.7V to 6.54 volts, while the TX voltage stays solid at 9.2V whole time. Battery, converter and TX screen in VR are all cool, no sign of heat anywhere.

I used the "LM2577 DC-DC Adjustable Step-up Power Converter Module" from Amazon, $5, lol.

Note, if you try this, first use a voltmeter to set the DC output close to 9.5 volts BEFORE hooking it up to TX, mine arrived set at 18 Volts.