Spektrum Interference - Help
 

Hope you guys can help I am having no end of problems with interference for the last month or more. I thought it was down to my Acoms 2.4 set and maybe some of it was. I have since bought a Spektrum DX3S 2.4 Ghz in the hope that it will solve my woe's. As you are probably already guest I still have interference. Below is my full spec and some pictures of my layout

B44
Spektrum DX3S
SR3300T Spektrum Receiver
JR Digital Z9000S Servo
Novak GTB (Not sure if it is Spread Spektrum Optimized)
Intellect Lipo's
Nosram Storm 4 Star

I have a Xcelorin 4.5T combo but it is away getting fixed so I cannot try this to rule out the GTB

Anyone got any ideas on what it can be ? Why did novak introduce a spread spektrum GTB was it for interference issues ?

How can I tell if my GTB is spektrum optimized

i think sometimes people have to run a power cap from the receiver ? i might be wrong and im sure someone will correct me if i am :lol:

Thanks Someone mentioned this at the club but they were not sure. Are you saying if the GTB is not Spektrum optimized then I need a cap ?

Can anyone elaborate ?

I run a NON-Spektrum optimizef GTB, and have done for over a year and have never had interference.....

What servo are you running? Ive heard of people having p[roblems with some servos that draw too much current under load/have too high a torque rating..

are the lipos new have you tried another set of lipos

i had similar problems with a faulty battery pack


colin

Hi all

The power cap on the reciver helps with HIGH Amp Draws from servo (as when you nail it with a good servo the BEC in the spedo cannot cope with all the amps and there for the volts drop and your reciver goes into failsafe , what a cap dose is it stores a little bit of power for when your voltage drops , and when it dose it compensates until your esc gives the full power back , dont know if explained it clearly enough its hard to explain :D , try a powercap , wheres your arial i know carbon fiber can sometimes interfear , even with 2.4 i put my arial up a straw or i get interferance.

John

The servo is a JR Z9000s its a 10th scale super fast one

JR's fastest racing servo ever uses a specially designed anti-distortion case and tight metal gear train to give racers the perfect blend of lightning quick responsiveness and amazing torque.
Specifications:
Type: Ultra High Speed
Torque: 128 oz/in @ 6V
Speed: .06/60 degrees @ 6V
Dimensions: 0.83x1.59x1.50 in
Weight: 2.2 oz
Gears: Metal Gears

The cells are brand new I have two packs the same and the problem is the same with both but I will tray a set from another racer next week

So what is the point in the spread spektrum GTB ?

The spektrum GTB has something faster in it.....some FET related thing I think?

Do you have another servo you could try? Id put 50p on it that your servo might be at fault...

Thanks John
See my pics for the layout and arial location etc .... Pictures speak better than words lol This cap sounds like a good place to start and cheap i suspect ! bit skint after £175 DX3S ! Were can I get one ?

So your confident on the servo being the culprit lol

I do have another servo but I like this servo its super fast 0.06 ! The other one is a hitec which is 0.1

But if thats it then its got to go !

Would prefere the cap option if it meant i could keep it ?

I have Telemetry temp sensor on the motor maybe that is drawing a bit if current ?

Tim, are you at Teesside this weekend? :eh?: If you are come and see me.

G

I am not racing but I did fancy a pop up ! will come and see you and bring the car

Thanks

Does it still glitch when not being driven? :eh?:

G

It glitches only when driven and its not major its a mix of a sudden pulse of power and sometimes a full on out of control but alway just for a 1-2 seconds max. I can sometimes get 2-3 laps in ok then it glitches

still sounds like the power cap will solve that:)

Tim, bring it ready to run round the track then, we'll have a go before finals or after maybe, see if we can fix it :D

G

I'm with Wraggy too, good chance a power cap will fix it. I run one in EVERY car now.

G

If it's not solved by a power cap , im sure northy will be able to sort it out (laughs nervously)

I will bring it up ! Thanks !

Any chance this could be motor related?.. Just a thought..?Have you tried a different motor?

Hi Tim,

this was why I was asking what servo you were using on Tue night. It may draw too much current from the BEC when steering and accelerating, which strangles the current to the receiver, causing interference. A Cap would prevent this by providing a source of power for the receiver under these conditions.


I know you dont use a Personal Transponder......... if you did, it would probably amplify the problem, as thats more power draw form the BEC.

CP.

In answer to the spread spektrum optimized GTB question, it's to do with FET switching speed as coSie said. 2.4ghz radio gear runs at a higher frequency, so the esc's FET's switch at a matched frequency which means it responds more efficiently, and consiquently runs a little cooler. This doesn't change the feel/performance significantly, only it's efficiency really.

Standard GTB's are limited on the FET switching speed to better match the lower 27mhz/40mhz speeds of the older radio systems. A standard GTB will work perfectly happily with 2.4ghz/27mhz/40mhz, however the spread spektrum optimized version will only run with 2.4ghz radio gear.

I'm pretty sure that right anyway!

glitching
 

that servo must be just like me after 8 pints...suffering with a glitch!!!!!

Run a cap on the receiver, most ESC's can suffer with power drainage with digital servo's, the cap will help stabilise it. It don't get the same 'interference' as you would, with an analogue system, but the receivers are prone to power drops and spikes.

Just get a power cap of an old ESC, and a servo fly lead, and make sure you keep the lead short, or you could buy the Spektrum on, £6.

NorTech sell em too :)
http://nor-tech.gforceimages.net/sto...roducts_id=116

Everyone loves NorTech :D

Just one more thing to check. I had all new kit in a B4 at a Newbury event. It had all the symptoms of the above. Due to the time between races and running two classes, I could only change one thing and test in a heat. Needless to say I only figured it out in time for the final.

Turned out it was the Banana (Corally) connector that went into the LiPo. The spring gripped the inside of the LiPo fine, but it wasn't gripping the pole and therefore intermittent connection.

Worth checking that first.;)

Also, I have used many different Spektrum receivers. The 3500 Micro was fantastic, as I could tuck that in with the rest of the wires and didn't have to worry about signal loss or having an aerial. With the new DSM2's I had loss of signal and had to install an aerial tube. Also, I noticed on the instructions to not put a cap on the tube and have the bare cable section protruding.

The above costs nothing and whilst it's the most unlikely, it's worth checking, just in case.

Ok thanks all !
I will get a cap from northy on Sunday !
I will check the corrally connectors and maybe just get some new ones !

Thanks for all the help ! I will post on here what fixed it fingers crossed !

No need for new connectors.;) Just a very small screw driver (jewellers one) poke between the fins and bend them a little further out. You'll know if it's the case: as before you'll feel it move slighlty and after it will be tight as a <insert forum friendly metaphor>

But as said before - Rare, but worth a shot.

Good luck.

Well it appears to be fixed ! I got a cap from Northy (thanks !) and it was fine all night. I did have one glitch but it was when my cells went dead (mixed them up opps) and this kind of proves it was a low voltage thing !

I'm facing the same problems with my DX3R. I'm having a signal loss every now and then.

Since I'm running an X6 recently, could the problem be that the electronics interfere because they are much closer to each other?

I dind't have this problem using my B4 with the same electronics.

I'm also going to use a cap in the receiver and see what happens.

Would this cap be suffisiant ?http://i2.photobucket.com/albums/y3/qadiche/SP-B.jpg