[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Paparazzi-devel] Interference issue

From: Roman Nikitin
Subject: [Paparazzi-devel] Interference issue
Date: Thu, 21 Apr 2011 07:24:27 +0100



thanks for a good explanation. Now everything works just fine. The problem is as I think big interferences between the paparazzi components and R/C. I am using EasyGlider and there is not a lot of space in the canopy. So all the parts are pretty close together. After I did a ground tests with the autopilot on in manual mode (R/C aerial is down) I could walk 20-30 m from the A/C only, after that the radio signal becomes very  weak and the flight mode will be switched automatically to AUTO1.  In the case the ap is unconnected the R/C range is more then 100m with the aerial down.  I am using 35MHz controller because my XBee is running at  2.4GHz.


For me it seems to be a problem with magnetic interferences within the canopy. Is it right? Has anybody ideas what can be done to avoid it? I found that it the car industry it is done with aluminium foil that will be grounded after that. I never done something similar and  have no idea how it could work with uncovered PCBs.


Any help would be appreciated.






Von: address@hidden [] Im Auftrag von David Conger
Gesendet: Mittwoch, 20. April 2011 18:54
An: address@hidden
Cc: Manuel Linourtner; Tom Richardson; Chris Toomer
Betreff: Re: [Paparazzi-devel] PPM wiring




The only time to worry about 168 or 328 is when you must choose the right file to program it (done by the person who assembles it). After don't worry about it. 


Let's go high level and maybe I can help you and others about this. 


Your Tx outputs a combined signal with all 8 (or more) channels. The autopilot needs all of these also as one combined signal. Your Receiver has only individual channel outputs (labled 1,2,...8) ... so, how do you get each individual PPM signal to the autopilot as only a single combined signal? Well, Chris (hendrix) found us a way a long time ago using an ATMEGA to take each individual one and combine it and output it. So you'll find many intputs on the encoder and a single 3 wire output. Make sense? 


How you wire from your Rx to the Encoder is your way of manipulating that combined signal. If you want Ch5 on the combined signal to be a 3-pos switch that is say ch7 on the Tx then take the ch7 output from the Rx and connect it to the Ch5 input on the encoder. Voila. Ch5 is that 3-pos switch now as far as the autopilot knows. 


Best regards,

David Conger/PPZUAV


On Apr 10, 2011, at 11:02 AM, Roman Nikitin wrote:

Hi all,


I did use ATmega168 PPM encoder before and it seems to be damaged now. So I ordered a newer one that is ATmega328. I am confused a bit, it is not clear how to wire it?! Three wires (+,-, signal) goes to the ap board, for another wires there is one +, one - , and 8 holes for the signals. I found this picture  and I am not sure now, how should I do a wiring. In 168 version each of the channels had power, ground and signal  which are going to R/C receiver. Does it mean here that the R/C receiver will be powered just from one wire with one ground wire?! , and for other channels signal wires must be connected only?!


Please, I need some help with it. I  have not found any instructions how to do it.


It would be nice to have a better picture with some instructions to it.  Just sent it to my private e-mail if you have some or may be a link.

Thank you.




Bristol Institute of Technology

University of the West of England

Aerospace Systems Engineering

tel. +44 (0) 7760806643


<image002.png>Please consider the environment before printing this email.



Paparazzi-devel mailing list


reply via email to

[Prev in Thread] Current Thread [Next in Thread]