servo lead chokes, are they useful
 

Hi,

now a days everybody puts stuff into their plane, emcotec's powerboxes fancy switches and regulators all microp controlled... even a simple powerLED and servo lead chokes.
I myself are an electronics engineer and I can't find a reason why these chokes are for.
Which frequencies do they block? where do the "to be blocked" signels come from?
I hate flying around dead weight just to ease my mind.
If it is for glitches servo's produce, they should be located near the servo... but they are located near the receiver.
If it is for "other" glitches, one should locate them near the device that produces them, for instance an electronic ignition unit or so..
or just make a fix so no glitches are produced (metal to metal)
Most receivers have the highest sensitivity for spurious signals in the IF band (455 kHz). It's a fairly low frequency so the radiation impedance of the cricuits after the choke is quite high and reactive, the choke will have a hard time to cool it down.
So why

Input would be welcome

RE: servo lead chokes, are they useful
 

Maybe they are thought to be of use because most rc leads are not twisted and thougth to be subject to hysteresis. But the voltages and power are low and I doubt this occurs.

RE: servo lead chokes, are they useful
 

I am also an electronics engineer and have found both chokes and twisting to be essentially useless, from both a theoretical aspect and a practical one, on servo and battery leads. Now twisting does neaten (is neaten a word?) up the wiring a bit. The only time a choke or iron core would help is if the electronic circuitry in the servo was going into some type of high frequency oscillation which is most unlikely. Now there could be an occasion if someone was using and ESC that was not well designed that would feed noise back to the receiver. In that case, a choke might help.

RE: servo lead chokes, are they useful
 

The servo chokes are used mostly on gassers that tend to develop RF problems, usually on the throttle servo. I was getting a lot of glitching on one of my gassers and tried the choke on my throttle servo, no help. I then changed the RX and what do you know, problem solved. I found the antenna was falling off that RX on the inside of the case so problem found. I still have that choke but I never have figured out if it works/helps or not. As engeneers would you guys call RF noise and electrical problem or not?? That's all the chokes were used for.

RE: servo lead chokes, are they useful
 

For gas ignition systems is there a capacitor option to reduce RF like they used on cars with mechanical points years ago?

RE: servo lead chokes, are they useful
 

Resistor spark plugs is about it

RE: servo lead chokes, are they useful
 

I just got hit hard by RF for the first time. Reason, dumbass person doing a dumbass set up. I have gotten away with breaking the rules for so long I thought I could always get away with it but I got caught. I had my throttle servo mounted right next to the coil on my G-62 right on the fire wall using metal control rod. I asked for it and got bit real hard, it could have been real ugly but the plane was OK. I'm now setting up to the rules again and havng no problems. The old rules to set up a gasser were writen by much wiser people then myself and it only took one time for me to learn my lesson.[&o]

RE: servo lead chokes, are they useful
 

RF can be a real sneaker.

You can get away with a bad installation for a while but one of these days it will get you

RE: servo lead chokes, are they useful
 

LOL Rodney I don't know how many times I've heard about twisting servo wires preventing interference.

Its great for phone and network cable, useless for servos.