hello guys,
i need to know please about some RC cars and helicopters that doesn't have any antennas, how does these system works ?
we see a LED in the front of the controller
It is actually an infra-red LED that emits light of a specific wavelength not visible to the human eye (that's why you don't see it light up). There is a receiver on the RC vehicle.
aha ok so how much distance can this cover ?
I think that would depend on lots of conditions like the wavelength of light, how bright the ambient light is etc.
I haven't played with this myself so I can't really comment. All I know is that I can stand in my kitchen and turn on my TV in the family room (20ft/6m), which uses the same principles.
I've had a few IR "RC" helicopters. RC for "Remote Control", the marketing guys hoping you'll be thinking "radio control".
30 feet is just about the max, if you make sure the IR LED in the transmitter is pointed at the vehicle, and nothing gets in the way.
aha so u don't suggest this IR method to be used if i need about more than 30 feet ?
sure !
I'd say no more than 23 feet, and nothing between emitter and the car
To get more than about 30 feet, you'll need either a set of really powerful IR emitters, or a lens to focus an IR LED. Then you need to point right at the sensor. People are building "Laser" tag (not really LASERs) sets using IR LEDs pulsed at 1A peak current with good glass lenses and getting up to 1000 feet in extreme cases, hundreds of feet with more modest efforts. And of course you can buy official Lazer Tag brand gear (Lazer Tag: Team Ops and now Lazer Tag: Phoenix LTX) that can go something like 350ft or more.
Do NOT use an IR LASER. Bad idea. Eye damage can result, and you won't see a bright light so won't reflexively blink or look away.
IR generally works for indoor control, and they will work outdoor at night,or on very cloudy days when theres no sun.
Sunlight totally swamps the receivers and they dont work.
Range is pretty limited.
ok , i had a RC helicopter, the Controller of it had 3 LEDs pointed in different angles (why?)
and i used to point the remote anywhere not necessary to the helicopter and i never saw a receiver on it
something like this but different wave transmitter : http://www.gadgetgalaxy.com.au/609-3%20400.jpg
walls reflect light and IR, that's why these toys work well indoor
and there is a IR receiver on it
ok i found it it's like this one : http://www.led1.de/shop/images/thumbnail/produkte/popup/IR-Modul.jpg
but can someone tell me where is the antenna then in a normal transmitter and receiver on a helicopter like this ? http://www.cobratoys.com/v/vspfiles/assets/images/m11_yellow.jpg
is it the bar at the top ?
IR works only when transmitter & receivers are in line of sight. That is when they "see" each other. Basically this is a light so the IR rays reflect from many objects like walls and glass doors. But the IR receiver get disturbed when it gets IR rays from any other sources like Tube light, SUN or other IR remotes. Try operating two IR remotes at a time. None will work. This is also the way to " Jam" any IR based receiver.
iknowvator:
IR works only when transmitter & receivers are in line of sight. That is when they "see" each other. Basically this is a light so the IR rays reflect from many objects like walls and glass doors. But the IR receiver get disturbed when it gets IR rays from any other sources like Tube light, SUN or other IR remotes. Try operating two IR remotes at a time. None will work. This is also the way to " Jam" any IR based receiver.
right some TVs doesn't work if the remote is not exactly in face of receiver but some do work is it because the receiver is in a way it can receive from many directions ?
Radio antennas tend to be dependent on the wavelength used - though they can be a lot
smaller. A clever design of RC toy would use part of its structure as the antenna.
The bar at the top of the copter pictured is the gyro-stabiliser, it controls the blade pitch,
nothing to do with electronics.
MarkT:
Radio antennas tend to be dependent on the wavelength used - though they can be a lot
smaller. A clever design of RC toy would use part of its structure as the antenna.The bar at the top of the copter pictured is the gyro-stabiliser, it controls the blade pitch,
nothing to do with electronics.
aha ok thanks for the info