FQ777-124 Pocket Drone

I tested a 7E with the range mod set all the way down to 100uW (1/10 mW) using DSMX and an MCPX, I got 31M range with it. I was amazed how far it transmitted on such low power. I would think you could fly most micro quads safely at 10mW under any circumstances.

BirdBarber wrote: Your voltage regulator may be overheating and causing unstable voltage, it's only rated to about 200ma total from what I've been told. And that's when running on NIMh which don't heat up the regulator nearly as much as a LiPo because they are closer to the final regulated voltage. So it doesn't have a whole lot of power to spare for the add in boards.

Maybe you should try setting the transmit power down to 10mw or 30mw and see if it helps, it should still have enough transmitter range to fly it beyond visual range.I've heard other people say you need to add a 2nd voltage regulator if you're going to use 100mw or above, but I haven't verified this myself.

See this post for details: www.deviationtx.com/forum/7-development/...dule?start=780#52623

Thanks a lot! you think it's better to put the nimh batteries instead of lipo? can decrease the range dsm2\x protocol with nimh batteries??

@paglia

The extra voltage of the LiPo is all wasted in the form of heat and doesn't increase the power or transmit time, it only makes the voltage regulator run hotter. The range would be identical at the same transmit power because the voltage regulator supplies 3.3V to the transmitter with either battery. The only difference is that NiMh start with a lower voltage so the voltage regulator has less excess voltage to get rid of in the form of waste heat. So it's possible to set the transmit power a little higher using NiMh before the voltage regulator overheats because it isn't working as hard.

With DSM2 / DSMX you are using the stock CYRF module inside the transmitter instead of the add in NRF24L01. If you haven't done the 'range mod' to the 7E, then it's CYRF module has a non adjustable 10mW transmit power. In stock form the 7E CYRF module isn't adjustable like the NRF24L01 module or the CYRF modules in other Devo models. So the actual transmit power of DSM2/X is identical on a stock 7E with either battery, it just runs hotter with a LiPo.

Did dropping the transmit power make any difference? Looking at goebish's last 2 posts it looks like you should set the transmit power to '10mW' or lower since the '3mW'' & '10mW' settings are actually putting out 20mW, which is more than enough for this quad. If you use the '1mW' setting then it is actually putting out 5mW, which is 1mW higher than the stock transmitter that came with the quad.

Thanks for explanation BigBarber, I have make the diode CYRF mod, and I have read many user run their 7e with 2s lipo, sometime even 3s, i thought it was for output power, but if not for this then why put lipo battery?

So I have tried 10mw and it seems fly good now!

I am running 30mw and it is fine. No issues here.
My setup is 7E ultimate with eBay battery.

The battery can't effect the output power. And only the mah rating of the battery matters for the run time since excess voltage is thrown away as waste heat. Some LiPo batteries, like in the previous post have higher mah rating than cheaper NiMh, so they will run longer, but the transmitter will run hotter. Some transmitters get away with it and some don't. The LiPo are also faster to charge. The 3-in-1 / 4-in-1 thread goes into it quite a bit. You can see from your own experience that your transmitter overheats if you turn the transmit power up running a LiPo. Myself, I run Eneloop 1900mah NiMh batteries, but they are somewhat expensive. Cheaper NiMh batteries are only 1500mah or less despite having claims of higher ratings.

A LiFe battery is in-between NiMh and LiPo in voltage. So it will charge fast and will overheat the transmitter a little, but not nearly as much as a LiPo.

The 7E has a cheap 'linear' voltage regulator. It gets rid of excess voltage as heat. It's also a small regulator, so it doesn't really have much extra current output for add-in boards. Some other transmitters use a 'switching' voltage regulator. They use a more complex circuit that gets rid of excess voltage more efficiently and don't waste it as heat. In those transmitters a higher voltage will extend the run time of the transmitter since power isn't wasted as heat. But no battery will increase the transmit power, the transceiver modules only see an identical regulated 3.3V no matter what battery you are running.

A battery with a very small continuous output current (ma or 'C' rating) could in theory cause the transmitter to not run at full power, but all battery types for the 7E have way more than enough output current to run it properly, so it's not an issue.

@gobish

I reinstalled your deviation-devo8-v5.0.0-999a4f1.dfu and filesystem on an 8S with discreet NRF24L01+PA+LNA and gave it 6 test flights. Everything worked great with zero problems or lag. I tested all modes: normal, flip, RTH and headless many many times. I would say it's ready to go as paglia's problems were with the voltage regulator and not the new protocol.

This little quad sure is zippy and a blast to fly on rainy days. Thanks to all that worked on the protocol.

Awesome! Good to hear it's working well for you guys. Thanks for all the work, goebish!

Hello guys, it seems work all right but have a question for you, have you tried scale to 125? seems to work and be more responsive, can you confirm this?

Thanks a lot for the hard work, guys! I can now finally fly my FQ777 with a Devo 7e.

Hi goebish,

does the support for FQ777-124 included in the nightly builds or do I need to use the deviation-devo10-v5.0.0-4f78a00 from the Dropbox link above?
Thanks.

Fantastic. Thank you so much.
The pocket drone now binds both with Devo 7e and Devo 10 using the latest nightly (2ce0f46).

i have FQ777-124 , with green board pcb. cant bind DEVO 7e.

the board use LT5910 chip.