I don't think they will allow you to make a transmitter to do this. Also see "type approved in Lebanon".
Because that radio is carefully designed by trained engineers, extensively tested, and approved.
but why what is the reason, if it is just like the FPV used on RC airplanes ?
so is it possible to build a small talkie walkie similar a bit to the one used in the racing world ?
what about the toys i guess it's very low frequency
doesn't cover much more than 20meters or something
Because some one who does not know what they are doing can cause havoc interfering with vital communications of the Police and Military. Governments do not need that extra hassle.If you do know what you are doing you can apply for type approval which means your design is independently tested to make sure there is no interference outside the band you are using and that it is being manufactured in a professional way. Of course you pay for that.If you want to learn then there is always the Amateur or Ham license but there are restrictions on the use you can put to that. RC airplanes use a specific band and the equipment has to be type approved. Imagine you were flying your plane and it was brought down by someone messing about with an FM transmitter. You would not be pleased and it could kill someone.
how to define the frequency i want to work on ?
is it by making calculations and defining what cap, resistors and inductors
Quotehow to define the frequency i want to work on ?It depends on the frequency range you are working in.Quoteis it by making calculations and defining what cap, resistors and inductors For low frequencies say less than 30MHz you can do this although the value of all these components will change with temperature with careful design you can keep it down to manageable proportions. For higher frequencies it is more complex and a simple free running oscillator will not be stable enough. There are different techniques like heterodyning, crystal oscillators and mixers, and the use of phase locked loops to name but three techniques.
it is more efficient to use the crystal oscillators for example
You have to modulate it so one way with FM is to start with an 8MHz crystal, frequency modulate it and multiply it up to the FM band.
If you need the functionality rather then the project experience you might consider something like this pre-made with digital frequency control.http://www.ebay.com/itm/Naztech-N3030-Hi-Fi-Digital-Universal-FM-Transmitter-/251416114395?pt=US_FM_Transmitters&hash=item3a899174db
i don't really understand what you mean by multiply it up to the FM band, seems a bit advanced thing
Quote from: retrolefty on Jan 16, 2014, 10:58 pm If you need the functionality rather then the project experience you might consider something like this pre-made with digital frequency control.http://www.ebay.com/itm/Naztech-N3030-Hi-Fi-Digital-Universal-FM-Transmitter-/251416114395?pt=US_FM_Transmitters&hash=item3a899174dbit's about the project and learning, if i wanted to just buy then i won't be on this forum :S
it's about the project and learning, if i wanted to just buy then i won't be on this forum :S