rcplumberpilot

what do you wrap around servo leads to kill interferance from ing system[X(]

spaceworm

Back in the day, ferrite beads were used to supress interference with long servo leads. Also, the servo leads were twisted. I have not heard of their use in a long time. Perhaps someone else has better inputs.

bcchi

Do not wrap anything around the servo leads. You need to find out what is causing the problem,not hide from it.
Need more info. What engine,what ignition what spark plug what radio. When does it bother on start up or range check?.2.4 or 72?What hae you done to try and fix the problem?
BCCHI

f4urak

I have had the same problem, i am using a 2.4 ghz radio. The engine is a evolution 26gt. the engine has done it since it was brand new. never could get it to go away, i noted when doing range checks full throttle, but it would sometimes do it close also. I ended up buying futaba filter extension, that have a ferrite ring and another filter built into them, they made the problems go away, but i would still like to solve this problem.

All Day Dan

My Feedback: (5)

Here is some advice for you two guys that I give to everyone with interference problems.
You should always keep every component our ignition system and radio system separated by at least 12 inches or as much as possible. Never have any metallic object in that 12 inch isolation area including a metal pushrod to the engine and especially a throttle servo. This advice holds true weather you experience interference or not on the ground or if someone else tells you that it's BS because they have gotten away not doing it. It will catch up with them one of these days. Dan.

bcchi

Very true.
BCCHI

pe reivers

Make that Me Too.
The only occurrence with modern well shieldedignitionswas when metallic pushrods were used. Get rid of the rods, and use Nyrods or similar, and problems are over.
Magneto ignitions are worse, and need to eliminate airborne AND wired interference. Anything acting as an antenna pics up RFI disturbance.
To keep those pulses away from the receiver, the servo lead is coiled through a ferrite ring to form an inductive coil. The same, albeit to a lesser degree, can be obtained by twisting the servo leads and fix the twist with a heat gun.
This twisting has become a habit in all my intalls. Further advantage is that the leads get more flexible by the twisting, and wires are less prone to break by the ever present engine vibration.

f4urak

My installation was in a funtana x with a evo 26, the nearest radio componant to the engine was the aileron servo extensions, just behind them were the throttle and choke servos, i had a short peice of steel rod connected to ny-rod for both throttle and choke. I had to make a hatch in the tail to install reciever and battery which was fine because that is where the a/c came into CG. I have wondered if the carbon wing tube could be posing a problem with this somehow acting as an antenna. Also has anyone seen where you can buy an new shielded ignition lead? I had a crash the first flight with the new engine before i put filter extensions on the servos due to radio interference, in the crash the HT lead was chopped in half, i slpiced the lead with a small copper rod, some enviro-tape and a peice of shielding from a large peice of ham radio coax. i soldered the shielding to the existing shielding. The RF intereference is the same as it was when the engine was new. and it seems to work good, but i would like to replace it with new. Also is it possible that the shielding is not connected inside the igntion unit, my RF problem seems very bad compared to set-ups the rest of the gas airplanes at our flying field are using. They have their recievers around 12" from the nearest igniton component and do not have any problems. In my setup the servo extensions came within about 15 inches of the ignition switch and i was still getting interference at wide open throttle.

pe reivers

If the shielding has an opening that is a mere half of the wavelength, interference will peek through and cause airborne radiation!
Having said that, the shielding must be earthed at all times for several reasons. Mainly because it serves as negative line, regardless of how you push the cap on; which brings me to the next source of radiation: The plug cap.
If it is not pushed on all the way, severe interference may occur. The caps of the CM6 plugs are not easy to push on. You need to use a pushing/twisting motion. As long as the cap shielding has a slight gap, the cap is not fully pushed home! Come to think of it, this may have been your problem from day one! Pls forgive me if I am wrong.

tryan02

Just got past this problem myself. Always blame the ignition it puts out way more power at a certain frequency than your TX does. I found a fraid end on my spark plug wire the braid was cut and later found that the can on the plug was not the greatest either. I changed to an RCEXL ignition completely wrapped the braid in plastic spiral wrap and the plug booot fit way better.

I fixed my wire and it seemed fine till the next damp day then it returned, I replaced the ignition before I took the time to clamp the boot to the plug one of those days you just get so frustrated you throw parts at it till its fixed things.

mine was great till you hit full throttle and would go into a roll!!!!

Wingman26

It looks something like this! Watch the control surfaces. New ignition module coming.

[youtube]http://www.youtube.com/watch?v=oKwqy3vEa0s[/youtube]

f4urak

My plug cap has always been seated all the way, i used a high quality peice of shielding, that is very dense weave. I have done a fair amount of trouble shooting and dealing with RF interference at my job, i am a mechanic on a Chinook heli. This one i just havent been able to figure out.

f4urak

Ok i just pulled the cover off of the ignition unit, off of my ignition unit, then peeled the silicone away and found a small solid wire broken that is soldered to the circuit board and then is wrapped around the shielding, im hoping this could be the problem, evidently the ignition was still getting a ground because it had spark, i will repair this wire and try it out when i get the airplane together.

f4urak

I plugged in my igntion and there is a nice spark at the spark plug and a nice spark where the wire is broken, i can see that it has been sparking at the broken wire for awhile it is rounded off on the ends. this means there was high voltage returning through my shielding to jump the gap at the igniton box. I also noted that you can twist the shielding pretty easily at the ignition box, and that is why it is broken, i possibly broke that wire when it was brand new just moving the lead around, the wire is very small and it is solid so it is easily broken with just a few bends. There is absolutely no slack in the wire, whoever soldered it together at the factory could have left a small amount of slack there.

pe reivers

It should be worth a test if the interference goes away after you fix the broken lead. Check out with Horizon though.
Is this an ICU or a Vlach ignition?

rcplumberpilot

i have a mt 50 rcexel box bpmr6a plug spectrum 2.4 and throutle servo up frount with motor, did a check with a ing tester and above 2000 rpm tail and ruder servos go crazzie tail is dual servo ive seen those magnet like rings around servo leads though i need them would love help new to 30% planes thanks GOD BLESS

spaceworm

This is your problem!! "...throutle servo up frount with motor..." Move it back 12 inches and use a plastic pushrod to control the engine throttle. NO metal clevises. No radio electronics of any kind within 12 inches of ignition components. Stop trying to fix the problem with wraps or ferrite beads (magnet like rings).

rcplumberpilot

okay thanks for the help will do it

bcchi

If the ground wire from circuit board was broken ,that was your problem.That is if you spark plug cap is all the way on the plug and grounding good.
Your will have a spark at the plug with broken shielding. The ignition will seek a ground at the hall sensor Spark will jump from the Negative wire on the hall sensor to the magnet in the prop hub.This can knock out your hall sensor in some cases, in just a short time.Also cause massive RFI.
BCCHI

fujiman

My Feedback: (133)

hi yee all, i'm needing some help. is there direct replacement Iridium plug for a ngk #BMR6A? i've checked on the web with no success as of yet.

Antique

My Feedback: (4)

try sparkpugs.com
Only gasser I can think of that uses that plug is an old G23, most would use a BPMR.

fujiman

My Feedback: (133)

thanx antique for input. i'll try that link. the reason i'm going with the bmr6a ngk plug is the ign. plug boot calls for that plug. that said, i'm not sure if the bm6a plugs are the same size(?????) if you know try are would you let me know? i'm getting my ign. systems from "agape racing and engines", and the ign. unit is the rcexl. he lists the bmr6a plug as the one to use. the man at s/s ign. says the rcexl has a built in secondary resister in unit therefore you don't need a resister plug(????) wonder what the diff. is between the bpmr and bmr is??????? the bmr6a plug uses a gasket seat not a taper seat that i do know. wish i had a cross ref. chart!!!!!!!

Dr_Chuckie

I'm having pretty much the same problem as rcplumberpilot. I have a Zenoah G20ei, Spectrum 2.4. I'm using a 4.8v Hydrimax battery for the ignition. Anything past half throttle causes the servos to glitch. Plug cap on tight. Already tried bypassing the kill switch. I disconnected the throttle linkage and still have the same problem. Next step is to try an FM receiver and see if that works any better. Another possibility may be the nosegear steering. Before changing out receivers I'll try disconnecting that as well.

rcplumberpilot

bpmr6a plugs were started for marine use an turned out to be good plugs so moved to small enguine and the bmr6 was for small cc motors for weedeaters chainsaws bla bla so fourth but both are 14mm plugs, bpm is the plug id number for thread size socket height and r is for heat raiting and 6 or 6a is the not realying what that was indecated for right know but o well just thought ill try to help a little

All Day Dan

My Feedback: (5)

If you guys that are having problems have digital cameras it would help a lot if you post images of your installations from front to rear and both sides. Dan.