hello can i fold an rc car antenna?

Hello im working on a project and im using a cheap rc card reciever n transmitter but the thing is i cant have any antenna pointing out of the enclousure , i tried wrapping the antenna arround a small acrilic tube and it didnt worked i chops up the range up to 1/2 is ithere any way i could get rid of that wire? thanks

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Tnnrguy7 years ago
yes- You can but the distance will be shorter to were ever your try to getthat signal.
What frequency is the controller transmitting at ? 

Steve
cupnoodles2 (author)  steveastrouk7 years ago
27 mhz :D is there any way to shorten it? appolo seems pretty sure that its atleast pretty damn hard :S
27 mhz is in the cb range.  If you can find a friend with an swr meter that also will work as a signal strength meter you can use that to measure the radiated signal as you trim the end of the antenna.  Radio Shack and lots of others used to sell a meter like this.  There was a little antenna you pulled out of the meter and it read a signal strength from that.  You will be tuning the antenna.

What you would need to do is start with a coiled antenna 1/4 the length of the wave length of 27 mhz and trim off pieces an inch at a time until the signal was the strongest.  THen that is the length that will radiate the most power.  If you trim off too much solder some more wire back on and go at it again.

1/4 wave of 27 mhz is a number I'll have to get back to you later on or you can google it.  I don't remember what the length is.
Looks like full wave on 27 is 11.11 meters. and quarter wave is 2.78 meters of wire.

Rolled into a coil can make it work like a longer or shorter antenna.  I would start with slightly more than 2.78 meters and go from there. 
Sorry, it is, even the ones on now are a big compromise. The length of the antenna should be about 1/4 wave 300E6 /27E6 or 2.8 METRES for perfect coupling, assuming you have a decent ground connection.

I am not an RF specialist, and I am sure there must be experts here with some suggestions for compact antennas.

The mobile phone works at  1000 x higher frequencies than you are using, so the antennae are over 1000 X smaller.
appolo7 years ago
Hi, all RF transmiters and receivers have to use some form of an antenna to transfer signals. It may be possible to reduce it's size by careful redesign. But the operating frequency of both very much predicts the dimensions of the antenna. Mobile phone antenna's have been made much smaller by the introduction of new design techniques known as 'Fractal Antenna's' do a Google search to see how they are designed and used. Which antenna do you need to conceal? Alternatively wrap it arround the enclosure itself and keep the wrap spaced out as much as possible...try that.  regards