Twitchity Hex - Oh boy, here we go again!


Senior Member
i was not sure what he was cooking. i thought it was maybe some kind of pastry at first but who would heat up a pastry like that. so maybe chicken on a stick?



Some guy in the desert
Wow, has it really been this long since I've given a hex update?

Could have sworn I updated this when I took it to Flite Fest. It collapsed down pretty well but did take about 10 minutes of effort to get it small enough to fit into my carry on:


When I arrived in Ohio it was another 15 minutes to re-assemble - the extra time was because one ESC power wire got pulled loose ("thankfully" it was a cold solder joint I had missed so no damage was done and I was able to fix the joint while I was at it...despite the rather crude soldering iron that was all my dad had on hand.) But I got it back together and ready to fly the day we arrived, was too late for a test flight but all seemed to check out.

The next day we had a family reunion and a number of people spotted the hex and asked about it. So I pulled it out and gave some people "rides" through the goggles as well as hooking the video RX to my parents big TV while flying LOS through the backyard. It was a HUGE hit. I did my best to get a few people sick with wild rides (hey, I was flying LOS it was easy!) but no lunches were lost ;)

The next morning I got my dad to spot for me and tried a bit of FPV in their backyard. My parents have a nice big 300' deep backyard...but with lots of trees. The trees don't have any branches until about 25' up though so I figured it would be fun to finally try flying around some trees. But with Flite Fest just a few days away I didn't want to risk breaking the hex and tried to take it really easy. Mostly I just managed to prove to myself that I need a LOT more practice flying around obstacles.

(I know I posted these videos in some thread sorry if you've seen it already.)

At Flite Fest the hex got far less attention than I expected. My bright pink knuckle quad with a controller no one recognized on the other hand made a lot of people stop and chat :D I never got to do any FPV at FliteFest because I didn't want to bother with frequency coordination...and I didn't even get around to flying the hex until late Saturday just before we were getting to leave. Mostly I felt I had to get it in the air since I had dragged the thing across the country :) Besides, there were lots of multis at FF but not many hexes, and very few multis flying acrobatically. So when someone questioned the setup on the hex and tried to convince me it would be better off with 5" props I felt compelled to prove him wrong. First 3/4 throttle punch out he made a little "woah" noise and grudgingly admitted the 2204 2300kv Cobras seemed to swing the 6" props just fine :) Big problem with flying it was keeping my concentration due to people asking me questions about it:

Upon return to AZ the hex was promptly unpacked, re-assembled...and pretty much left to gather dust. It was July and it was just too freaking hot to do much flying.

I've pulled it out and gotten ready to flash the latest firmware (oneshot and horizon have seen major improvements, and GPS assisted flight as been vastly improved so I'd love to try all that good stuff out.) But keep putting it off. I did make some "skirts" for it to hide the wiring and I know I posted about that...but I'm not sure what thread I must have posted those in.

Finally a few weeks ago two friends showed up to go flying and we got to do some FPV at the park. But the hex didn't want to play nice. Not sure what was up with it - put it in the air...felt good...then suddenly it did three flips and slammed into the ground with no input. Went to fly it again...and the video was gone. Didn't know what was up. Tried to fly it LOS...and it flew...but it scared me a few times just feeling like it wasn't responding right. Not sure what was up but something definitely wasn't right. So I grounded it for the day.

Since then I've been super crazy busy bringing our yard out of summer slumber and planting a garden for "AZ Summer" so haven't got to do any flying. I did come close to finally doing the firmware upgrade...but again chickened out at the last minute and got lazy.

Tonight I decided to figure out what the heck was wrong with the video.

Opened it up, and swapping some things around isolated the problem to the camera. Bummer. That's one of my nice Sony cams. That last crash didn't look THAT bad...what could be wrong with it. Let's take a look and see if we can figure it out!


Hmmm, nothing jumping out at me. Anyone else see anything wrong? Let's take a closer look.


Oh...I think I see the problem...anyone else? Let's try and make it more obvious....


Really hard to get an angle that shows of the legs on that crystal is broken!

Heat up the iron...little drop of solder on each end...melt them together....hey it works! Drop of hot glue on the legs and crystal to keep it from breaking right away again...still works...let's put it back together!

So it's ready to test again tomorrow. I expect massive failure. Because I'll have a nice big crowd. We're going to climb a little nearby "mountain" with a young professionals group my boss is president of. Figure I'll bring the Nighthawk 290 and the hex along and see how they do. The Nighthawk should have no issues...I just don't have many batteries for it. The Hex I've got plenty of packs...but with it being goofy last time it flew and this hack of a fix on the video...I'm not expecting much from it. Still...crashes make for good video right :D


Junior Member
Hey I am building a zmr 250 with pdb and a brain board. I am looking for help on how to set up the board with all of my hardware. Any help would be great thanks :)


Some guy in the desert
Yep, what he said. If you can be more specific about what you need help with I can certainly try to assist!


Some guy in the desert
Well, most of that is explained on the Brain site:

Motors connect to your ESC's like normal. ESC's connect to the "Servo" pins on the Brain. Since you only have for motors there's nothing fancy here. Fire up the GCS to see which motor position goes to which pin.

I don't have any FrSky gear so I can't really help much with the x8r. I'm guessing you want to run sbus and telemetry? You'll need 2 serial ports for that so you'll probably want to "UART" mode on the RX port with pins 8/7 as your RX/TX for s.bus and then on the main port you can hook your telemetry up off the RX/TX lines there.

The AV port is where you hookup your FPV gear - it's basically a video in and video out. So video comes out from your camera and goes to video in on the Brain, then video out from the Brain goes to video in on your VTX.

If you're running a GPS then you may be better off using the main port for GPS and putting telemetry off the flx port. But again I haven't messed with telemetry on the Brain yet since my only RX that can do telemetry fried before I got my brain board.

The more detailed your question though the more detailed of an answer I can give :D


Faster than a speeding face plant!
Connections for my fpv gear, motors/escs, and x8r

I would start a build thread listing your components and showing photos of your gear. You will get more help and all the newbies who are still trying to screw up the courage to start their own copter can follow along with your build and be inspired. :)


Some guy in the desert
Finally dusted the hex off again today. Few things going on with the Tau project and it inspired me to finally upgrade the Brain firmware to the latest release. I had been running my own build since I have the KISS set for oneshot and due to Brain not being in-tree with Tau it sometimes lags on getting new features. So rather than wait for an official build with oneshot I had made my own after Fujin brought oneshot from the Tau tree into the Brain tree. That was back in March.

Since then there's been a LOT of stuff fixed/upgraded/changed in Tau and Brain. Improvements to the OSD, flight stats, fixes for horizon mode, improved nav...and setting up oneshot is a lot easier now since GCS has been updated to accommodate it.

First I did the new flash. Was a fairly straightforward process, but ran into a minor issue calibrating the outputs due to this being a hex. Basically the problem was that the setup wizard tries to have you setup the output idle values before you get a chance to setup the hardware config - I had set it as a hex but there was never a chance to change the RX port to PPM+outputs to enable motors 5 and 6 so just had to trust that the same values I used for motors 1-4 were ok.

With the setup done I was ready to autotune this morning...or so I thought.

Turns out I forgot that I had originally used an afromini when I built this and Tau and *Flight have the motors going in opposite directions on this style of hex. You'll see in the video what this causes if you get it mixed up :)

With that figured out things worked, I was able to run autotune and got results similar to what I've seen before - so took it out front for a quick test and to try out the new "acroPlus" mode. (acroPlus basically disables the gyros at high stick movements giving you no stabilization and direct stick input control...scary but intriguing.)

So yeah, hex is alive again and I'm dying to get it out to fly somewhere with more room. Unfortunately the battery in my TX isn't holding a charge well anymore :( New pack will be here Tuesday (along with a second 9x thanks to HK putting them on sale for $22 the other day!) So I ended up spending the afternoon climbing a small mountain with my wife and daughter instead of flying. Fair enough trade :D


Some guy in the desert
As I already mentioned in the dRonin thread I've been lucky enough to test the new Seppuku flight controller that one of the dRonin dev's has been working on. Since there were already testers using them in planes and quads I figured it would be fun to put my sample into the hex.

The install went super easy, the through hole style wiring setup resulted in much cleaner wiring than the original BrainFPV board with it's tiny connectors and pigtails.

And it flies great. I had a friend who's a better pilot than me give it a go last weekend and he loved it. He was a bit was his first time flying a hex, he knew I can't get replacement arms, I have almost no camera tilt on it right now and he's used to flying with quite a bit of tilt, and my rates weren't setup the way he usually has his setup. Even so he was amazed at how great it flew for him given that it was on a stock unadjusted autotune tune. I'm still working on cleaning up the video but here's a tiny taste:


(Direct link if that doesn't work well: )

More details about Seppuku here:

I'll be posting more about it soon. The next release of dRonin should be out really soon and has a bunch of new features along with support for this new controller. Here's the "short" list:

Support for Seppuku flight controller added.
BrainFPV fixed a critical bug in the RE1 target which caused in-flight resets when there were glitches in the vertical sync signal.
Improved accuracy of BMP280 altimeters in the driver.
Accuracy of attitude estimation for on-screen display and leveling modes improved on F3/F4 targets.
Stabilization module improved to reject noise and compensate for jitter better.
Autotune improved: measurement consistency was increased and F3/F4 targets now capture advanced data that will be used in the next generation of the algorithm.
Preliminary support added for DShot 300/600/1200 on all targets.
Preliminary support for DAC audio on Seppuku target-- audio telemetry and "beep" alarms.
Added support for WS2811 LEDs on BrainRE1, Seppuku, Revolution, Quanton.
Added new "AcroDyne" flight mode that allows dynamic acceleration at high stick deflection.
Corrected an issue lowering telemetry link performance-- both directly attached USB and radio/serial links.
Camera tilt angle for reprojection can now be set using TxPID module.
Fixed a regression with CC3D PWM input and OneShot/high frequency output.
Improvements to ESC calibration safety and interoperability with recent BLHeli.
BrainRE1 was updated to use the proper buzzer infrastructure like other targets.
Improvements to input wizard and receiver activity framework.
RFM22B/TauLink/OpLink RSSI is now available as an RSSI source.
Removed the PicoC language and existing waypoint persistence mechanisms in anticipation of future work.
LightTelemetry improved for better utilization of slow telemetry links.
Usability: Setup wizard added support for additional receiver types (SRXL, iBus)
Usability: Input pane shows status of RC inputs.
Usability: Switches are shown better in Input Wizard.
Usability: Improved tool-tips and descriptions of UAV objects in many places.
Usability: GCS now prevents from being started multiple times at once and associated anomalous behavior.
Usability: Improvements to wiring diagrams in GCS.
Improvements to various behavior on Raspberry Pi / FlyingPIO target.
Infrastructure/developer improvements: cleanup, upgrade to Qt5.8, etc.
Various crashes and defects fixed in GCS.

I'm hoping I can get a DVR on it this weekend to show the OSD...going to be tricky though as we've got a pretty full weekend. But we'll see what I can pull off ;)

grnd flyr

The install went super easy, the through hole style wiring setup resulted in much cleaner wiring than the original BrainFPV board with it's tiny connectors and pigtails.

What PDB or other did you use here? Curious on the connections as I have one ordered too... :)

I'm hoping I can get a DVR on it this weekend to show the OSD...going to be tricky though as we've got a pretty full weekend. But we'll see what I can pull off ;)

Here's to hoping you have time :applause:


Some guy in the desert
What PDB or other did you use here? Curious on the connections as I have one ordered too... :)

The hex has a custom PDB I helped twitchity design that's part of the frame. It's a "dumb" pdb that doesn't have any active parts on it, but has pads to mount a 5v pololu voltage regulator which powers the FC.

Keep in mind this hex is 2 years old now, so other than the pre-release FC nothing on it is "latest and greatest" but it was 2 years ago when it was built :D 18a KISS esc's with 2204 Cobra 2300's. Back then PDB's were considerably less common and those that were out there were just dumb power distributions boards without regulators or other features yet!

Here's to hoping you have time :applause:

Well, I should be able to find time...just not sure if my friend the better pilot will have time or not ;) And they're predicting a touch of rain for this weekend :eek:

So...we'll see ;)


Some guy in the desert
The friend who was piloting it thought it was on 4s when he saw my first footage from it :D

Kind of tempted to try it on 4s one of these days...but it's crazy enough as is. Still 4s on 6 5" tri blades could be fun....

Been drizzling the past two hours but seems to have cleared up. Just got back from picking up the last connector I needed to rig up the $20 eachine DVR I got. Now that our local radio shack is closed it meant a 1 hour drive to spend $9 for two F/F RCA adapters :( Plus the cost of froyo at the shop next door so my daughter wouldn't complain about going along.

Kind of makes me wish I had just cut the wires and soldered the dvr in instead. But my long term plan is to build the DVR into the same case as the diversity receiver I'm building. So I don't want to use up too much length on the pigtails that came with it.


Wake up! Time to fly!
Yeah they deleted my local radio shack too. But it was tired. We always had questions. They always had answers.. "we dont stock that anymore did you try walmart. I could put in an online order for you if you just give me all of your personal information as well as six family members and two close friends emails and cell numbers."

I just bought one extension cable from Walmart that had both rca ends as well as an audio cable extension and fabricated my own permanent cable that has power to my goggles, connection and power to the DVR and headphones all in one harness.