yeah, that some strong wind.. you were not joking when you said you were in the mood to fly aggressive.. you smacked the cement a few good times. seems the frame is more than strong enough.. i guess i will have to rethink my take on full pdbs that are not protected.
if they can smack the cement with out issue.
I really wish I had caught the good crash on video if you thought that looked aggressive
Did another test flight with the same battery and same tune but with the DAL 6040 props. They're definitely a step down in performance from the HQ 6045's - but they did give me considerably longer flight time. So for a beginner their resilience and extra flight time could be a big plus. Then again their lack of "punch" could hurt as well since it's a lot harder to recover from flips/rolls without better throttle management. As with anything in aviation you always have to give up something to gain something else
Still have an hour until that video is done processing...and then another hour or two to upload it. Probably won't be done in time for me to post it here tonight so anyone anxious to see it - subscribe to my youtube channel
In the meantime...let's take a closer look at that AIO board shall we? While waiting on my pack to recharge I decided to take a look and see what would be involved in reflashing these built in ESC's.
First off...ok, maybe I was a bit reckless that flight...pack was reading 120F and when I first pulled it off that first cell was at 3.01 :black_eyed:
After letting it rest for awhile they all came back to 3.41 though and on the charger it sucked down 1341mah so maybe not quite as abusive as it seemed at first
So removing the AIO board was pretty easy. Just undo 4-6 wire connectors (6 stock, 5 if you've already removed the LED...4 if you've removed the LED and VTX) then 8 5.5mm nuts. Though my 5.5mm driver didn't fit them as well as I'd like, but my 5mm was too big and my 4mm was too small
Then just pull it off. I found it helps if you push on the top of the XT60 a bit because it's a VERY tight fit through the plate.
Speaking of the XT60...I can't say if there's any glue on it or not...the conformal coating makes it kind of hard to tell, it could be glue but is probably just the coating. Either way that XT is ON THERE and I'm not at all worried about it coming loose. Also visible are the two power outputs and their corresponding switches as well as a "video" connector though it's unused in the stock build. There's a matching one on the other side so I'm guessing they're just passthrough traces as the manual says if you use them to use filtering...and it doesn't look like any undocumented filtering is hiding on the board.
The main processor is a good old STM32F1 and the sensors (MPU-6050 and standard mag) are on a little daughter board that has two layers of foam tape under it. I'm guessing that was done to minimize vibrations to the sensors...though given my experience with motos wii board I question the necessity. emax probably just found it easier and cheaper to add a daughterboard, flat flex cable, 2 connectors and some tape than it was to have someone customize the filtering/tune to work well with hard mounted senors. Heck this thing is running 3500 looptime out of the box
The ESC's are indeed SiLabs. So not sure why I'm getting that idle twitching with oneshot as the silabs have hardware PWM and should be immune to that. Also means I now get to learn how to flash SiLabs as I've yet to tackle that! Woo Hoo new tricks for me!
Just look at that mess though. Most of what you see on there is ESC. Each ESC has 6 large FET's they're closest to the motor connectors. Then a long row of resistors and caps, and closer to the processor chips some fet drivers then a few more passives (resistors/caps) towards the center. There are also LED's for each ESC that I didn't even notice until I took this apart...more on them in a minute. Oh and it's all covered in that conformal coating. Great for moisture/dust resistance so I can't really fault emax for adding it. But hell for trying to reflash things. The programming header for the lower left ESC is the four pads to the right of the processor.
On this one it's the four pads just below the big green cap.
Here they're to the right of the processor again:
Thought I got a shot of all four sets of ESC programming pads....but apparently I lost track. Oh well, it will be apart again soon
Here's the one thing I really wish emax had done differently. Those two big things above and to the right of the blue switch are the main 5v regulators. Basically they're the BEC in this thing. To the left of them just above the USB plug appears to be the 3v regulator...I can't say for sure since I can't read the markings through the coating but it looks right and makes sense. I suspect the switch just disables that regulator which effectively disables the flight controller part of the circuit since that runs at 3v. The SiLabs chips on the ESC's should run at 3v as well...but probably each have their own regulator which I just can't tell apart from the FET drivers due to the coating. (and honestly because I didn't think to look for them.)
Why do I wish this was done differently? Because those linear regulators are horribly inefficient compared to a switching regulator like the pololu's. Even on 3S the heat on this part of the board kind of freaks me out. Just plugging a pack into the board and letting it set for <5 minutes I get a reading of 110F off the bottom of the board in this area. It doesn't really get any hotter in flight...but sure had me worried the first few times I plugged it in.
On the other hand switching regulators are noisier. So for FPV they'd necessitate better filtering on the power/video circuits for the camera/VTX. But since they're not even using the traces on the board...I dunno. This just starts to feel tossed together rather than well engineered by emax. From what I've heard they were focused on hitting their price point of $200 retail. So with that in mind linear regs make a lot of sense. This wasn't designed to be an all out top end competitive racer. It was designed to be a $200 entry level racer. And to be completely fair it meets that goal and meets it very well. For $200 you'd have a hard time building a better setup for a beginner to get up in the air with successfully and quickly.
The connector to the right of the switch is where the ESC signal lines are brought out. And the connector to the right of that is where the buzzer lines are brought out. I need to swing by radio shack and pick up a buzzer tomorrow...both to show how to attach one and because as my flights today showed...I can't be trusted to fly without one when my battery beepers are all busted (and I've about quite buying them since I go through them so quickly!)
This is kind of a repeat of an earlier shot...but a bit wider. The power plug/switch on the right are for the VTX, the set on the left are for the LED's. The connector to the left of the LED power connector is the "video" connector that isn't used and described in the docs as "FPV Camera Connector. Please use filter to reduce video signal noise when power and signal are connected" leading me to suspect it's just a pass through to the matching connector on the other end. Will try to confirm next time I have this apart.
Speaking of connectors...here's the side of the board opposite from the USB connector. On the right is a SWD connector...why they bothered to include that I can't even begin to fathom. It's really only useful to people who need to run a debugger against live code running on the STM chip. Even Naze and Sparky don't bother with connectors for it and just give bare pads.
To the left of that is the main RX connector. It points up instead of out and there's a cutout in the plate above it so you don't have to have wires sticking out for it. (why they didn't do that for the buzzer connector and the vbat I can't begin to guess.)
To the left of that is the vbat connector for battery voltage monitoring...I'm honestly surprised they did it this way instead of just wiring it to the battery line instead to keep the wiring clean. Seems like a horrible oversight on emax's part. Especially with the connector facing out so using it means wires sticking out of the frame.
Left of that and not very visible are two bare pads for forcing the bootloader. As little as those are used they're still used more than the SWD connector so it would have made more sense to put a connector on those than the SWD. Odd.
Left of that are the three standard R/G/B LED's used on a normal Naze32 for status:
And on the front size we have another power connector with a switch to enable/disable it...that isn't used by default. Also another matching and unused "FPV Camera Connector"
With it apart I finally noticed that each ESC has it's own power LED. So here's a shot showing those lit up:
What I didn't find was any UART connectors...I know there's info on how to setup an OSD and sbus/spek sat on RCG so there must be a way to access one somewhere...but I'm going to have to do some more digging to figure that out. I'm guessing they just use cleanflight to remap those to the PWM input pins on the RX connector but can't confirm that yet.
If I come across as critical or disappointed it's not my intention. This is a very nice entry level 250 class race quad capable of swinging 6" props. I'm just not much of an "entry level" kind of guy at this point and have a hard time looking at something with that in mind
Despite the bigger motors this really isn't a competitor to the Vortex which is the closest comparison I can think of. And really it's not a fair comparison with the Vortex being more than twice as expensive.
And thanks to the FT forum going down for a bit while I was typing this up I actually can share the video of the flight with the DAL props:
That's on the same setup as the earlier video with the HQ prop's (and my earlier flight on the stock props that I didn't catch on video.) The DAL's are definitely lower performance than HQ's and lower quality...it took three layers of tape on one of them to get it to balance! (but on the other hand two of them didn't take any tape) But while the DAL's feel weaker in the air I have to admit I did get almost twice the flight time out of them off the same battery pack - and didn't drain it as low this time. So the DAL's aren't horrible...but they're still going into my stash of "beginner" props I use to train friends with rather than the stash of props I go to first for my own flying.
I may try and get BLheli 14 flashed on these ESC's tomorrow. But I'm also itching to try this guy FPV...and try CF with a better tune...will just have to see how the wind and humidity are tomorrow to see what I end up doing
