Simple 433mhz antennas?

[raptor am2]

Hello, I'm new to this forum and looking for help to get any range out of my 433mhz pair.
The project I'm trying to use them in, should allow a Infra red S107 helicopter to work on RF, whilst having as low component count as possible, and be easy to reproduce by others.

The size of the antenna on the transmitter doesn't really matter, however the antenna on the receiver needs to be as light weight/small as it can be, but sill have a range of 10+ meters. Would this be possible?

As far as i can tell there is no suitable ground plate in the Heli or transmitter, could one be made with a rectangle of bare PCB/aluminum foil?

So far these are the sketches that I have (i am aware that the receiver needs another resistor, and that the transmitter needs some form of shield)
View attachment 63966
View attachment 63964
View attachment 63965

All suggestions are appreciated, thanks in advance

 

[StudentSA]

The technical term for a straight wire antenna is a "monopole antenna". The ideal size of a monopole is 0.25*wavelength. The wavelength can be calculated directly from the frequency of transmission as : wavelength( in meters) = 300/frequency( in MHz). Thus your wavelength is roughly 0.7m and 0.25*0.7 = 0.175m. Therefore a 17.5cm wire would be ideal for maximum range. As far as ground planes go, a good ground plane is always best. however just connecting to the circuit ground should surfice otherwise you can build a aluminium type one. You can on the transmitter side connect ground to the person holding the transmitter to enhance the ground plane significantly.

 

[raptor am2]

Thank you very much for your reply, it is greatly appreciated.
I just checked and it turns out that I had cut the antennas at 15cm instead of the 17.5cm required
Now it flies perfectly after changing the antennas to the correct length, and using the helicopters chassis as ground.

Thanks for the advice on using the person as a ground plate, i would never have thought of doing that, and it makes so much scene too

 

[audioguru]

My micro RC airplanes and helicopter use 2.4GHz. The range is farther than I can see. The antenna length is about 3cm (a little more than 1").

My micro RC helicopter has an electronic gyroscope so it goes straight without turning unless I turn it by steering it. New RC micro airplanes have a few gyros so they also go straight and automatically adjust for air turbulance and wind.