Receiver Antenna Length

[DavidAL]

I am currious, when setting up a helicopter, what do you do with the receiver antenna? Can you cut it short or leave its length and do what with the extra? I want to feed mine through an antenna whip and have the end of the antenna at the end of the whip, but what do I do with all the extra antenna that is between the receiver and the antenna whip????????????? Please help with any comments..

Thank you
David :confused:

[tdswan]

I definately don't recommend cutting the antenna at all, what i do on my T-rex is run it in small fuel line down to the skid with zip ties at bothe ends so it doesn't get pulled, and then wrap it around the landing gear struts. Then I zip tie or tape the end down. With a micro heli, chances are you're not going to get out of range with this setup provided your radio's a good one. definately do a range check just in case. Also make sure the reciever and antenna don't run anywhere near your ESC. I have friends who got glitches with this setup.

[DavidAL]

Thank you, actually really good guess as to heli size. I am trying to learn on a Blade CP. The only reason why I have started to consider running the antenna through an antenna whip is to get it away from the 4 in 1 and to get it unwrapped from the carbon fiber legs and landing gear. My heli does sometime glitch and I was hoping that running it out on a whip would solve this problem. I have read a couple of times to get the antenna off of the landing gear rods to solve this problem. I have also heard that there is no problem with the antenna wrapped around the skids and that this does not cause any problems. :rolleyes:

Thank you
David

[tdswan]

Yes, E-Flight says there's no problems with it wrapped on the skid, that's why I tried it on my T-Rex. It worked well for me, but I made sure that reciever was on the opposite side of the ESC. On a BCP, I haven't heard of glitches with them, only had one closer friend with one and he didn't seem to have any trouble. Also take a look at where you are flying....flourescent lighting has a tendancy to give off some sort of a frequency, power lines, especially high-voltage transmission lines can interfere. I'm running a PCM system on my Raptor and had a radio hit once near some transmission lines. It's a real bad sinking feeling when the throttle drops to idle even for that split second! Lucky it was only once. Some guys have tried a ferrite ring in-line with the servo wires, also. They just wrap them around it once. I'm not sure where you get one, I haven't needed it but it's a thought. Glitches are tough to track down, sometimes the only thing you can do is keep experimenting and moving things around.

Good Luck.

[DavidAL]

Thanks again for some good info. What is a ferrite ring?? Also, I think I tracked down my glitch. I coiled up the antenna and laid it out on the reciever side of the 4 in 1 and ran the rest through a whip I bought. Looks a lot nicer. Also had to take off my blades (had to replace them anyway) and decided to range check my transmitter and play a bit. I know it sounds wierd , but when I rest my transmitter on my leg it glitches. I played with it for awhile and noticed that I could reproduce this glitch on purpose. It has to do with hitting a certain spot on the battery tray door of the transmitter I got, I think. I hope I can find a way to fix this because of the nature of the glitch. It usually causes the Heli to spool up pretty good before stopping. Not having had it off of the ground yet, it really freaked me out when it glitched the other day and lifted off the ground a foot and a half and then set itself down just fine. :eek:

Thak you
David

[Motions]

If your using the stock Tx, that where your glitches are coming from most likely. There are a lot of complaints about this. I use my Futaba Tx and never get glitches anymore.

As for the antenna, I have mine wrapped around the skid and have never had any problems. I have had a couple experiences where the wind has taken the heli off to a distance that I could barely see it, and never lost signal.

You can see from the photo how I have my antenna wrapped.

[rcfan]

Never, EVER, cut a receiver's antenna; manufacturers have gone to great lengths (no pun intended) to ensure you're Rx is tuned to the correct band it operates at. Shortening the antenna may result in reduced range (caused by loss of power and efficiency), radio glitches and other problems usually resulting in a crash.

Route the antenna away from any metal-on-metal parts, especially moving ones like bearings; keep away from carbon parts as well, such as most landing skids on small helis. Don't wrap your antenna around trying to squeeze into a small area, this will usually reduce range and create glitches, same as if it were cut. Especially don't wrap antenna around skids since you don't want to be landing on it often!! :eek:

Whatever you do, make sure that you don't fly with a loose antenna since it will definitely be sucked into one of the rotors causing a crash. There are alternatives available in the form of stub or base-loaded antennas. These usually will diminish range a bit, but will allow you to mount antenna in almost anywhere. If you do, make sure you get one for the proper wavelength your Rx operates in. Here's some (mini) examples for 72 MHz:

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DeeTee Mini: http://www.deeteeenterprises.com/NS.DeeTee.MiniAntennas.php
http://www.deeteeenterprises.com/images/DeeTee.Ant.1a.Orig.jpg

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Tech Models Mini: http://www.deeteeenterprises.com/NS.Azzar.BaseLoaded.Antenna.php
http://www.deeteeenterprises.com/images/TMP.Antennas.2a.jpg

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Mini power antenna: http://www.modefosheli.com/inc/sdetail/1234
http://j.b5z.net/i/u/2041425/i/zzzzzaxzz_ezr.jpg


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For larger helis, look for Deans antennas: http://www.deeteeenterprises.com/NS.Deans.Micro.Antennas.php