lownslo

I would like to know what is a "choke" on a "Y" extension? I am going to build my Fly Baby kit this winter and I will have 2 servos in the tail for the elevator,l and 2 in the wing. Do these work? Are they really necessary? It will be a 4.8 volt system. ....... thanks in advance.... lownslo

SitNFly

My Feedback: (54)

Choke is a capacitor installed in the servo lead to block high frequency noise from being transmitted back along the lead to the receiver. If designed correctly, they do work. Can't answer whether they are really necessary. Only way is to try a normal lead and see if you have any glitch problems. With today's high quality radio equipment, it's usually not a problem.

modeltronics

My Feedback: (27)

A choke is NOT a capacitor, it is an inductor.

SitNFly

My Feedback: (54)

Oops. Correct you are, bad I am.

dirtybird

My Feedback: (5)

I have been flying a 1/3 scale FLY Baby bipe with four servos in the wings,two servos on the elevator and a throttle cut servo as well as a throttle servo. Two of the wing servos are digital. I have found no need for chokes.
Make sure the Y harnesses are heavy duty with gold plated contacts if you can find them. I saw an ad in RCM for heavy duty Y harnesses with twisted leads and gold plated contacts but I don't remember where.
Chokes are a hold over from the early days of RC and are no longer needed if you are not into digital servos. Even then I doubt they will help much.

lownslo

Thanks for the replies guys!! I happened to be "window shopping" before I read dirtybird's reply. Without knowing his sugguestion I found some Y's, other extensions with 20 guage wire, and gold plated connector! They are at Servo City. http://www.servocity.com/html/24__servo_extensions.html This page shows several 24 inch extensions at resonable prices. ...... lownslo

Lynx

Actually a choke is a simple term for anything that absorbs RF energy. Capacitors and standard inductors can be used as chokes. What is typically refered to as a choke is simply a ring of special material that acts as an inductor at high frequencies. You see them around keyboard cables all the time, though, those are much bigger than those used in RC. They're most effective for preventing a servo's feedback from interferening with the receivers transmitter range. At RC frequencies, capacitors are actually more effective and smaller/lighter than inductors or ring chokes, but they're seldom used for some reason.