I just thought like the propeller thread why not have a thread that helps all of us to understand the radio we talk so much about better .
Q 1 ) How does a transmitter work on the inside and what type of communication is use to translate your stick movement to the RF Board ?
Q 2) When we say AM,FM , PCM , 2.4G etc what are we referring to ?
Q 3) When there is interference what do we mean ?
I know to some it may be elementary like what Sherlock Holmes used to say ;D .
The aim of this thread is to educate a newbie .
Lets try to keep the explanation as layman as possible with simple understandable language
It would be great if some inputs are given like :
1) Why do we do a range check with the antenna down ?
2) Will uneven ground affect range when checked along ground ?
3)Why do we get better range in air vertically where as the range is lower when checked horizontally along ground ?
4) Is it better to hold the Tx in such a way that the antenna is vertical or horizontal in relation to the ground ?
5) what should happen if the receiver is powered on without the Tx being on.
Toooooooo many questions :D :D
Guys one need not answer all of them let pool our experience and knowledge.
Sai
Mr. Sai, I really appreciate your Thinking. there are some Questions which on reading looks very simple, but when asked to answer........i think one should be aware of simple basics of radios and electronics before opting thing. I remember, one day i was asked a simple Q by one of my friend who is a pilot in Airforce and use to fly Helis. the Questions were:
1. HOW A TANK TURNS?
2. WHAT IS THE RPM OF A HELICOPTER BLADES? (NOT RC)
the Question seems to be simple for me and within seconds i replied, Tank turns with the help of a joy stick, and helicopter blades RPM should be around 10000 RPM. Approximating the RPM is quiet common but there was another Q on my Tank Reply, which i was not able to answer, because that was too technical. Which i know now ;D
Anyway , i will try to google out for answers. :D
Sandeep
Quote from: rcforall on August 14, 2009, 12:34:20 PM
4) Is it better to hold the Tx in such a way that the antenna is vertical or horizontal in relation to the ground ?
Sai
The reason I have asked this question was that
"I was told by an Radio expert who also flies RC that in case you feel your plane has lost range then move towards it with the antenna parallel to the ground not vertical "
Why would be interesting to hear from experts here.
sai
??? ??? ???
No One willing to help beginners with their knowledge
We had so many arguments about conversion , 2.4 G etc .
This is just the extension of that
Sai
Quote from: rcforall on August 14, 2009, 02:01:57 PM
"I was told by an Radio expert who also flies RC that in case you feel your plane has lost range then move towards it with the antenna parallel to the ground not vertical "
The radio expert is 100% right.
If you were able to see the complete RF field radiated from your TX antenna it will be like the shape of a donut (Or in native terms - like a Vada). The center hole of the donut is where you hold the antenna vertical to the ground. Now, the RF field is the weakest at the points directly above the antenna and is strongest at the points perpendicular to the antenna.
Now, when your model is loosing the signal, try to align the antenna so that the model falls in the strong RF signal region. I would slightly refine the suggestion made - "In case you feel your plane has lost range then move towards it showing the antenna's length to the model."
Here are few pictures of the radiation pattern of the whip antenna used in our TX. Note that the antenna is at the center of the donut shape.
Ismail ,
That is great keep it coming ;D ;D
Continuing with what Ismail is pointing out, the general recommendation is to keep the antenna pointing slightly down towards the ground (assuming the model is flying somewhere at a 45 to 60 degree angle with respect to the ground, in front of you).
In short what you guys are saying is expose as much of the antenna to the model and not just the tip correct .
Anwar ,
What is the right way to fly in terms of the antenna when flying 2.4 G
Sai
I guess exposing as much of the *length* of the antenna to the model is the way to do it. Avoid pointing the tip directly at the model.
And this applies to 2.4 also.
Quote from: anwar on August 14, 2009, 08:33:58 PM
Continuing with what Ismail is pointing out, the general recommendation is to keep the antenna pointing slightly down towards the ground (assuming the model is flying somewhere at a 45 to 60 degree angle with respect to the ground, in front of you).
Or, keep the antenna perpendicular to the ground. May be this is the reason why the flyers with tray type TX have the antenna sticking straight at their face.
Guys there are questions other than Antenna directions as well :o ;D ;D
Quote from: izmile on August 14, 2009, 10:06:44 PM
Or, keep the antenna perpendicular to the ground. May be this is the reason why the flyers with tray type TX have the antenna sticking straight at their face.
Yep, as long as you are not in the habit of flying directly overhead a lot :P