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Oct 04, 2016, 12:47 AM
Registered User
SeByDocKy's Avatar
Quote:
Originally Posted by vapgames
Ok, here's a brownout problem fix - remove the board connector and connect RX directly battery voltage:



ran through 2 batteries now, nothing has blown up yet
It's definitively interesting .... it probably means than the builtin Voltage regulator on the FC is guilty ....
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Oct 04, 2016, 04:06 AM
Registered User
Confirmed. Cutting or desoldering the center + pin between the Rx and the F/C boards - then running a wire directly from the LIPO's red + wire, greatly reduced but did not completely eliminate the receiver brown-out issue. The root cause is that the Rx used is a Superior Hobby SRP8 and is designed to run off 5v minimum. The F/C has a built-in in regulator that further steps down the LIPO voltage to around 3.6v even at full charge. Powering the Rx directly from the LIPO bypasses the unnecessary regulation and 'most' of my flights are now problem free.

This 380mAH LIPO worked well on it.

The protection ring is beyond fragile. They really need to make it out of nylon.

One concern is that, if the U.FL antenna is knocked off, the VTx may burn up so I added a dab of hot glue to keep it on. A clover leaf would be better. This one has a U.FL end but the top antenna fitting is too heavy - they need to make a light-weight version of it.

I found the PIDs to be sloppy in acro and bouncy in angle mode. The following values were more dialed in for me. In my case there was also lot of yaw and pitch drift so I solved it by increasing the RC dead zone a good bit.
Last edited by patricklupo; Oct 04, 2016 at 04:28 AM.
Oct 04, 2016, 06:05 AM
Registered User
Quote:
Originally Posted by patricklupo
greatly reduced but did not completely eliminate the receiver brown-out issue.
That's odd i haven't encountered any brown outs after the fix, flying till it can no longer lift.

Quote:
Originally Posted by patricklupo
The protection ring is beyond fragile. They really need to make it out of nylon.
Yep, tried glueing mine, but it just kept breaking in more places, so my x73 now looks like this:


Which kinda defeats the whole purpose of buying this model.
Using H8 props, with reduced weight and smaller props i can now use 260mah batteries.
Oct 04, 2016, 06:08 AM
Vids: YouTube.com/FyreSG
FyreSG's Avatar
Thread OP
Quote:
Originally Posted by patricklupo
... The root cause is that the Rx used is a Superior Hobby SRP8 and is designed to run off 5v minimum...
...
the VTx may burn up so I added a dab of hot glue to keep it on.
Last check, SRP8 is PPM while this one is SBUS. Are you sure?


Wouldn't the heat from the VTX melt the dab of hot glue?
Oct 04, 2016, 09:25 AM
Registered User
Quote:
Originally Posted by FyreSG
I don't think I raised any new, interesting points. But I do have some flight footages that you guys may like.

https://www.youtube.com/watch?v=uMk9uyv6cvg

I showed the binding procedure (to my FrSKY X9D+) at 7:50 of the video.
Thank you a lot for your very instructive vidéo.
Now, I am able to bind himself the RX of this bird.
She fly well.
Regards.
Oct 04, 2016, 10:38 AM
Registered User
My X73 Run with PPM and DasMikro Flysky Receiver.
A Little bit tricky...
Oct 04, 2016, 11:10 AM
Registered User
Quote:
Originally Posted by FyreSG
Last check, SRP8 is PPM while this one is SBUS. Are you sure?


Wouldn't the heat from the VTX melt the dab of hot glue?
You're right, the SRP8 is PPM but the chip layout looks identical so likely the same board design and 5v min voltage.

The 25Mw VTx doesn't get warm enough to melt hot glue.
Oct 04, 2016, 11:44 AM
Registered User
The sbus Receiver haven't a PPM Output Signal. The wiring go to PA3 at the STM32 Chip (Uart2 RC CH4 = sbus).
I solder a PPM Receiver to PA0 = RC CH1
Oct 04, 2016, 12:55 PM
Registered User
SeByDocKy's Avatar
Quote:
Originally Posted by FyreSG
Last check, SRP8 is PPM while this one is SBUS. Are you sure?


Wouldn't the heat from the VTX melt the dab of hot glue?
so it's the SRS8 with SBUS connexion
Oct 04, 2016, 05:15 PM
Destroyer of G-10
askman's Avatar
I had same issue with power cut. tried 600mah and it worked for a bit but as soon as voltage drops a bit, it shut down. I will try to bypass the reg. I have it loaded with beta flight and it flies fine otherwise. cracked the ring unpluging the usb cable. lol

I actually got tired of it, and I wired the camera to my kids micro hexa that we picked up for 20 bucks. it is actually working well and fly smoothly. The camera works well , so I may pick up another camera unit. or sell the x73 frame.
Oct 05, 2016, 09:10 AM
Vids: YouTube.com/FyreSG
FyreSG's Avatar
Thread OP
Quote:
Originally Posted by patricklupo
...
The 25Mw VTx doesn't get warm enough to melt hot glue.
I am using hot glue to secure the backplate (not at the antenna) but it doesn't stick after a few flights. Maybe it's the weather over here.
Quote:
Originally Posted by askman
I had same issue with power cut. tried 600mah and it worked for a bit but as soon as voltage drops a bit, it shut down...
I am still unsure if the shutdown was caused by the LVC safety mechanism, or the loss of RX signal due to insufficient voltage to the RX, or both. From what I have experienced, it does appear to be "both".
Oct 05, 2016, 12:16 PM
Destroyer of G-10
askman's Avatar
I set the LVC to really low value in beta flight,so probably RX is culprit for me. since my 20 buck hexa flies fine with it, I am not too impressed.
Oct 06, 2016, 07:12 AM
Vids: YouTube.com/FyreSG
FyreSG's Avatar
Thread OP

Official response from the manufacturer via Banggood


Banggood and their manufacturer returned from their 1-week holiday, and they replied to my unexpected shutdown fault report. I'm sure some of you may disagree with their report (and doubt if I got it right) so please refer to their actual reply:

"接收机是3.5v就可以了。不是自动关机!在暴力飞行的时候一定要注意,电池的放电倍率。低放电倍率会使 飞机在飞行时,电池电压下降很多,导致系统复位。还有,用户不能更换其他电机。我们常规飞行25c足以,暴 力飞,越大越好了。还有,系统复位也是电池电压保护,我们特意设置的,3.7v "

I hope my translation is accurate:

The RX only needs 3.5V. The X73 does not automatically shutdown! During aggressive flight the pilot must take note of the rate that the battery discharges. If the battery voltage drops too much, it will cause *system reset. And, pilot cannot change to other motors. For our normal flight, battery capable of 25C will be sufficient, but for aggressive flight, battery with higher discharge rate will be better. And, system reset is to protect the battery, which we intentionally set at 3.7V.

* Could refer to the FC or RX


Please let me know if you have more questions. I'll relay to them.
Oct 06, 2016, 10:32 AM
Registered User
SeByDocKy's Avatar
Quote:
Originally Posted by FyreSG
Banggood and their manufacturer returned from their 1-week holiday, and they replied to my unexpected shutdown fault report. I'm sure some of you may disagree with their report (and doubt if I got it right) so please refer to their actual reply:

"接收机是3.5v就可以了。不是自动关机!在暴力飞行的时候一定要注意,电池的放电倍率。低放电倍率会使 飞机在飞行时,电池电压下降很多,导致系统复位。还有,用户不能更换其他电机。我们常规飞行25c足以,暴 力飞,越大越好了。还有,系统复位也是电池电压保护,我们特意设置的,3.7v "

I hope my translation is accurate:

The RX only needs 3.5V. The X73 does not automatically shutdown! During aggressive flight the pilot must take note of the rate that the battery discharges. If the battery voltage drops too much, it will cause *system reset. And, pilot cannot change to other motors. For our normal flight, battery capable of 25C will be sufficient, but for aggressive flight, battery with higher discharge rate will be better. And, system reset is to protect the battery, which we intentionally set at 3.7V.

* Could refer to the FC or RX


Please let me know if you have more questions. I'll relay to them.


We all 100% disagree of course ... Happens with 30C even 45C battery ....
Oct 07, 2016, 01:52 PM
Registered User
TheMightyThor's Avatar
Quote:
Originally Posted by SteveCB
I thought I'd try again today, but I still cannot get mine to work. Mind you, it DID work, then it stopped (after trying to flash BetaFlight to it).

CF or BF says one of
Code:
STM32 Communication failed, wrong response, expected: 121 (0x79) received: 185 (0xb9)
Communication failed
No response from the bootloader, programming: FAILED
STM32 - timed out, programming: FAILED
while repeatedly clicking the Flash Firmware button.
I can bind to the FrSky receiver, but there is absolutely zero LED action. The board doesn't light up at all anymore.

Did I somehow fry mine?


Fixed. I am legit a jackass & wasted hours for nothing.

What did you do to fix it? i have the same problem after trying to flash with Cleanflight


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