Que

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rx connection
« on: January 24, 2017, 03:40:48 pm »
Hi Everyone,
 I am using an atom cc3d and an xt60 PDB. My problem is I can't figure out where to connect the lemon rx. There is only a 5v connection on the xt60 PDB and since I can't mount the Atom CC3D like a normal one it's not like I can just open it up and find a 3.3v in there.
 I've read in some threads that the Lemon rx can use the 5v pad, but other places I've read that 5v will burn it up. So where do I connect?
 I hope someone can shed some light on this for me.
 Thanks,

Que.

Re: rx connection
« Reply #1 on: January 24, 2017, 04:28:50 pm »
Are you using opto ESC? If so connect the 5v to cc3d and power the RX from cc3d. Your will have a wire going to cc3d for signal from the RX

https://librepilot.atlassian.net/wiki/plugins/servlet/mobile?contentId=14221325#content/view/14221325

One way of doing



« Last Edit: January 24, 2017, 10:08:01 pm by hwh »

Re: rx connection
« Reply #2 on: January 24, 2017, 05:26:24 pm »
First of all, find out what voltage you need for your receiver so you don't burn it up!

Most ESCs have a BEC in them that produces about 5v and that 5v feeds the FC.  The FC then feeds (direct connection) that 5v to the receiver.

The exception is when the receiver needs 3.3v.  In that case you need an external voltage regulator to reduce the 5v from the FC before it gets to the receiver.  You can also get 3.3v by doing some surgery on your FC since the FC does have 3.3v internally.  You cut the 5v going to the receiver, and splice internal 3.3v to the receiver.  Search the LP wiki for help.  :)

Que

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Re: rx connection
« Reply #3 on: January 24, 2017, 05:50:11 pm »
Yeah...I've been searching for 2 days trying to figure out what V for the lemon rx sat. :( I was hoping someone here had experience with it. Thank you for your responses. :)

Que

Que

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Re: rx connection
« Reply #4 on: January 24, 2017, 07:46:42 pm »
I found it...3.3 just like downtown...lol Going to use a v reducer to get what I need for now.

ernstock

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Re: rx connection
« Reply #5 on: January 24, 2017, 09:16:51 pm »
Yup , 3.3v.
I use a cheap and tiny 5v to 3.3v   .
Or :(presuming you are using a satellite direct,)
Some cc3d boards have an extra pair of flexi / main ports with 3,3v. , but I don't think I've seen a cc3d atom with these .
Or : the Hyperion satellite is rated 4.5 to 9.5v. Certainly happy on 5v and work good for me.

Que

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Re: rx connection
« Reply #6 on: January 24, 2017, 11:47:46 pm »
Thank you Earnstock.  :)

karla

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Re: rx connection
« Reply #7 on: January 25, 2017, 01:46:09 am »
Hi Que, since you already have a PDB that takes your LiPo down to 5V, Why not just take the 3.3V from the Atom board. No need for extra gadget to bring 5 down to 3.3v. I have this setup on 3 Helis. Works fine.
The Atom got the same connector as in the video below but more tiny. Soldering is not that difficult.

Que

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Re: rx connection
« Reply #8 on: January 25, 2017, 03:11:35 pm »
Good morning Karla,
 Looking at your Atom board I'm now wondering what version I have. Mine is encased in a smoke colored rectangle. I opened it up yesterday and couldn't locate a 3.3 pad on it anywhere.
 

hwh

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Re: rx connection
« Reply #9 on: January 26, 2017, 03:13:59 am »
Smoke colored rectangle ones are usually "mini-cc3d" instead of Atom.  They don't have the big servo connectors on them.  Functionally they're the same.   There are several people who made clones of the Atom or original cc3d with variations like that.

They all have 3.3v pads somewhere.  One of the two SBL (bootloader) pads is 3.3v.  Also the Chinese put pads on to load the initial firmware using an STLinkV2 or something similar.   These are usually labeled "OK+-".   The + one is usually 3.3v.

If you can't find one post a picture of the top and bottom of your board.

karla

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Re: rx connection
« Reply #10 on: January 26, 2017, 09:49:07 am »
Good morning Que,
Maybe these pictures can help you.
If not just post pictures of your board and hvh and other oracles here can spot the connectors for you :)
B t w, I did not do that video nor did I take these pictures.
I could show you where I soldiered them but then I need to remove the board and open it - not easy.
Hope it helps.

This link can explain more...
https://www.rcgroups.com/forums/showthread.php?2469869-Using-an-OpenPilot-CopterController-as-a-Rate-and-Auto-level-fixed-wing-stabiliser

Que

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Re: rx connection
« Reply #11 on: January 26, 2017, 02:07:28 pm »
Good morning Guys,
 Thank you for the solid info, it really helps. I'm glad I found this forum.  :) I did a little more research and I think this is a HK knock off. It's been a real pain. Getting this boxy little bugger into the frame and having enough room for everything else has been a nightmare. I only used it because I wanted to get this in the air. I think I'm just going to order one of the flat larger ones and change it out and just put this one aside for emergencies. lol...(multi rotor emergency)...
 This hobby has become an addiction!
« Last Edit: January 26, 2017, 02:19:06 pm by Que »