Lemon-RX Stabilizer Notes

Lemon-RX has released their DSMX 7 channel stabilizer, and user reports are coming in.  Backwards compatible with DSM2 it's 4.8 grams and $16.30.

Initial reports are good, and I think I'll get one to try out.  Here's some RC Groups notes by jj604:

1) The receiver binds very quickly in DXMX 22mS mode on my DX8.

2) Lemon have screwed up on their Aux2, 7 channel implementation. This is supposed to give you a 7 channel non-stabilised receiver using the bind connector for Aux2 and it does BUT if you have a servo plugged into Aux 2 when you power up the receiver always goes into bind mode! 
I tried it with couple of different servos. It may depend on the servos since the receiver is looking for a connection between signal and ground on the connector and it will be resistance dependent. In practice this is going to be pretty useless.

3) We now know how Aux 1 works. It DOES function as a normal output but also as a switch to turn the stabiliser ON and OFF. Kind of odd. In practice if you use Aux 1 to switch the stabiliser you really only have 5 control channels.

Overall it looks nice. I personally like the separation of stabilisation direction using 3x DIP switches and gain using the 0-100% pots over the Guardian bidirectional pot system. Very logical and easy to sort out. 

On the bench it seemed fairly sensitive but I have not had a chance to flight test it. I would regard this as a 5 channel stabilised receiver with remote On/Off and remote Gain. Very nice combo for many models. 6 control channels is going to require some thinking about in order to use Aux 1 for two separate functions.

I can't see the non-stabilised 7 channel option as being any use at all given the need to connect/disconnect a servo every time you use it.

Lemon-RX officer fmak notes:

I am sorry but we have to use AUX1 so that DX6i owner can use the stabilizer as well. During the stabilizer development it is required to test with DX6i, DX8, DX9 and DX18 so AUX1 is the only option for turning on or off the Gyro. Please let us know for any suggestions or comments. Thanks!

and

The currently stabilizer will work with DX6i since AUX3 is really an optional "variable gain" control. AUX1 will switch the stabilizer on / off and DX6i will work perfectly OK.

We cannot reserve Aux1 for dual servo aileron (use Y-connector please) because we have to design a stabilizer that also works for DX6i user. I hope this is sufficient as being the entry level, basic stabilizer.

However we are seeing more and more people requesting for flaperon. We will for sure look further into this. Thanks!

There's a good discussion of these points later in the thread.

Johnnymeg reports "It was very simple to get things situated and dialed in. It was very stable and held its heading and altitude very well. The pass through with my inputs was smooth and I didn't have to fight the Rx for control." and provides this video.

http://www.youtube.com/watch?v=ugn7_pp8rro

LemonRX Failsafe Notes

fmak2 clarified how the Lemon-RX failsafe works.

For Lemon Rx 8 channels receiver, failsafe is available for all channels and some user may found it useful (for robotics application or UAV). 

When bind plug is still plugged after successful binding, pressing the mem. button will cause the receiver to memorize all channels settings at the time the button is pressed for use in failsafe. If the failsafe is enabled correctly, green light should be on at the bottom of receiver. Press mem. button again while bind plug is plugged will cause the green light to turn off. This indicate the failsafe mode is disabled. Take the bind plug out before flying!
Even in the event of power disconnected, failsafe settings are still saved and will restore to its functions accordingly when power is provided. 

About failsafe enabled:
When the primary receiver and satellite receiver is unable to detect any RF signal for continuous time interval of approximately 3 seconds, all channels will be restored to the saved setting. At this point the receiver will try to find valid RF signal. If valid signal is detected, the receiver will use the valid signal immediately. 

About failsafe disabled:
When signal is lost for continuous time interval of approximately 3 seconds, all channels will have no output (all outputs are pulled to ground).
If you don't like failsafe, make sure green light is not on before flying!

And a note on CPPM/PPM and UART:

We aware that most people use CPPM/PPM for Adurino application, which is mostly used in quad-flyer or robotics. 

We had actually implemented CPPM/PPM sum output for 8 channels receiver. However CPPM/PPM sum is just too rough and troublesome for quad or drone application (including resolutions / number of channels/easy of implementation/ delays..etc.).  

It maybe better to switch to HUART which is currently available for 8 channels in the long run (high speed UART, 115200bps, 8N1). Use Adurino to read the HUART data directly. If you can check out our website, we have already simplify as much as we can for easy integration for Adurino or other embedded system application.