Jump to content
Sign in to follow this  
stpfl

big troubles in the setup

Recommended Posts

i bought a set contains a 1200mw transmitter with a receiver and a camera, i built the electronic in the plane but when i switch the transmitter on the receiver of 35mhz get huge error so that the plane wouldn't able to fly.

i tried many thing, to isolate the servos and receiver with alu foil, and other stuff, but i could not get the problems away.

later i will make a picture of the setup

i also tried it with another receiver in 35mhz

the video transmitter is in 1,2ghz

i hope there are some cool guys who can help me a little bit.

king regards

Share this post


Link to post
Share on other sites

It's sound exactly like me when I was trying a 434Mhz video tx with my 72MHZ r/c car receiver, I tried many things like you without success. But I know people who resolve this problem with a bypass filter. I don't know how to build that... Finally all the problem disappear when I change to 2.4Ghz. Sorry :(

Some frequency are not compatble togheter...

Edited by Vrflyer

Share this post


Link to post
Share on other sites

Could you try less power ? 1.2w is a lot. It may help you sort out where the problem is comming from. Any of the alu foil tricks or filters may just get swamped.

Terry

Share this post


Link to post
Share on other sites

Are you using a DC-DC converter (switching regulator) in your setup? I have had terrible luck with those interfering with my receivers. They make a lot of electrical noise, EMI, RFI, etc. Since then I've only used step-down linear regulators.

Also, I have had similar bad problems if a microcontroller was not isolated from the receiver and running at high frequency, like a few MHz or more. Some of this noise may have been resistive crosstalk through the battery.

Hope this helps.

Share this post


Link to post
Share on other sites

Did you already try some small ferrite-chokes where you wind 1 to 3 turns from the servo-cable onto? This helps much. IF NOT search for a discrete, passive "low-pass filter" via google and put one each on each servo-cable.

Greets

Share this post


Link to post
Share on other sites

setup.jpg

i took a picture of the setup..

i had no time to try some filter or something like this.

could you help me, can you give me a link of one of these filter which i could use

Share this post


Link to post
Share on other sites

I see two immediate problems. Your leads are all very long and the flight battery is being shared with the video equipment. Those two issues need to be addressed before you move on.

What is not known is how close you operate the Video Tx to the onboard R/C system. It must be sufficiently far away when using high power 1.2GHz equipment.

Share this post


Link to post
Share on other sites

hello!

i will try it with leads with shorter length. is there a problem sharing the flight battery with video equipment?

i tryed it with a seperatly battery just for the video, but there were the same problems.

i can take the transmitter 1 meter away from the 35mhz receiver but the situation isn't going to a better side

are there some guys who can show me some adabtable filters for receiver servos or whatever..

Sorry for the bad english.

i hope you can understand me.

Share this post


Link to post
Share on other sites
is there a problem sharing the flight battery with video equipment?

Doing that often results in interference problems. For some folks the video is affected, for others the R/C system is affected. Of course some have no problems at all, but from my observations, that is rare. I highly recommend that you do not share the video system battery with the R/C model. Once you get things working to your satisfaction, you can then attempt to share the battery.

Share this post


Link to post
Share on other sites

can i buy these filters everywhere?

- or plans to built it for myself?

the flight batt is not using for Bec (receiver servos). is that the reason that sharing the flight batt makes troubles?

but i have an opto regulator?

if i cannot solve the troubles i will sell the system to buy one of /www.blackwidowav.com

something like the 600mw package.

i heard thats good quality equitment.

because using 1,2ghz in our country is not really legaly.

Share this post


Link to post
Share on other sites

Hi stpfl.

If you are using the same power source ie flight battery to power you'r transmitter and flight motor you can expect problems. Does the video improve when you throttle off (turn the motor off)but still under r/c control?

Try using a totally isolated power supply for you'r video transmitter!

Edited by Johnstorm

Share this post


Link to post
Share on other sites
Hi stpfl.

If you are using the same power source ie flight battery to power you'r transmitter and flight motor you can expect problems. Does the video improve when you throttle off (turn the motor off)but still under r/c control?

Try using a totally isolated power supply for you'r video transmitter!

FWIW, I've always been sharing one battery (3s Lipo) for my motor (typically brushless running 8-16A), TX (600mW 2.4GHz), and camera.

These are the conditions under which I've had problems:

1) Trying to use a switching regulator to down-convert my voltage to a usable (for me) 5V. Very very bad for glitches. Real bad. I've switched quite happily to a linear reg and put on a small heatsink which has exposure to the passing airflow. The linear reg has a 350uF cap on the front side and a 22uF cap behind it.

2) Trying to run a PIC chip too fast (i.e. 8MHz clock). This was pretty bad, but somewhat better than the switching reg. The Pic, among other things, controls a Bob-3 video overlay board. I've switched to running the Pic at 125kHz clock, and it's now hunkey-dorey.

Under these conditions, I can't even detect additional glitch interference from the circuitry, even in my most extended rc range tests.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×