Antenna Tuning

[aperson]

how do i tune an antenna. its not from RS, im making my own. no i dont have a range problem, i just need something to do to my XMOD. thanks.

[aperson]

helloooooo... is anyone there? does anyone know how to "tune" an antenna. i thought i read some where that it had to be a multiple of whatever frequency you were using. im not that great in math, so whats a multiple?

[Shiporu]

hey aperson,

if yoo ever find out how to tune it, plz tell me!! I would like to have more range on xmod. I was thinking that if you rub it on the crystal or other frequency things, you better "tune" the attenna.... will it work? it works on magents and stuff...

-Shiporu

[neurokinetik]

To be safe, just make the antenna the same length or exactly twice as long as the stock one.

And no, rubbing the antenna on the crystal won't do anything.

[aperson]

ok thanks neuro. what if i make it 3 times longer? or do i have to do it in even numbers only?

[TypeZer0]

take the speed of light in either metric or imperial system (lets's say metric, so that woudl be 300,000,000 m/s) and divide it by the frequency (like 27.255 MHz for channel 6) but make sure you're dividing by hertz, not Megahertz so make turn that number into 27255000. what you'll get is the wavelength in whatever units you chose. in this example, it's 11 meters. the optimal length of the antenna is always some quarter of this wavelength like 1/2, 1/4, 1/8, 1/16. what i did was get the length (i used imperial system, aka feet miles etc) and keep dividing in half until you reach a reasonable length like 28 inches or something like that. make an antenna as close to that length as you can. dont' forget that the wire goign from teh actual antenna to the receiver board counts as part of this length too (correct me if i'm wrong)

[eetoi]

Whoa, typezer0, that flew right by me... I know this must sound like a stupid question, but, the 28 inch length you determined, would that supposedly match the wavelength of the signal? Is that why that length would work best? It seems a bit too long for the xmod, could I coil it inside the car?

[TypeZer0]

oh, that 28 inches was some number i remembered when my antenna on my controller snapped and i was looking for a suitable reoplacement. if it's too long, divide by 2. i don't recommend coiling it, spread it out so it would have a greater chance of "catching" the radio waves

[crusader4x]

When I fried the inductors in my Xmod, I purchased the inductor repair kit from atomicmods.com. One important part of the inductor replacement is "tuning" the range by making adjustments to the pot on near the inductors. Is this the "tuning" you're inquiring about?

[jaubery]

No. Tuning the ant. means adjusting its' length to match the wavelength of the signal it is receiveing.

[TypeZer0]

tuning the inductor (which i did back when i played with zips and bits and needed some adjustment after i dual/tri-celled them) changes the frequency it's tuned to i think. that should be like the last resort to fixing some kind of range problem. if you get good range, don't touch the inductor and play with the length of the antenna instead

[Shiporu]

will this "tune" attena work if yoo fried the pcb?

[aperson]

no. i already tried it on one of my rangeless PCBs and it dosnt help much at all.