RobertMP

I recently purchased a Magnum NX but havn't had much luck with it.
It all started when I had to burn-in the engine. It was dead! The glow plug was dead and after a replacement it ran smooth.
After a few tanks of fuel had been consumed by the engine I started slowly moving the car around.

Now my real problems began!
When the car was +10 meters from me it went bezerk and I lost control of the car.
I shut the engine down and started testing. It became apparent that the radio range was less than 10 meters.
I went to my local shop and they told me to replace the reciever. So I bought a new reciever. Didn't help!

I then purchased some really good batteries to see if the problem was related to battery power. Still no luck!

I then contacted a friend and we tried using his batteries and crystals... Still no improvement in range.

You might think it's the transmitter by now. Well so did I, so I ran out and bought a new transmitter. Still no luck!

I have now replaced crystals, transmitter, reciever and installed 2500mA batteries and it's still less than 10 meter range.

I really need some help. The "ohh this is fun experience" is turning into frustration!

I could have bought the biggest CEN RC car instead of all the money I proured into my Magnum, just to get it to work and it's still not working!

Edit: Changed sender to transmitter

diggernz

maybe its the transmitter. transmitter batteries OK? some xtals dont work with some radio geat. Its best to stick to all the same make in each model if you can.

RobertMP

woops. I named the transmitter the sender..

Other than that. I also installed the 2500mA batteries in the transmitter

SOILWORK

Check the servos...they could be glitching.

RobertMP

"glitching". Can you please explain what that is and how to test it?

SOILWORK

Put the truck on a stand and keep the transmitter off but turn on the reciever and move the servo wires and battery wires and see if the servos twitch. If there is twitching, use heat shrink tubing around the wires to help insulate from interference. This happened to my Nemesis, the battery wire was causing interference with the throttle servo and it would lock at wot. Somtimes it could be a simple thing as a couple of wires being to close together or if the wires are close to a metal component such as the throttle or brake linkage..I hope this is some help.

RobertMP

I will try that tonight!
Thx a lot for the info from your experiences.
I apriciate all the info I can get

SOILWORK

I forgot to add that somtimes, nitro engines when running can also cause some interference.

RobertMP

Ehh and how am I supposed to prevent that from giving me bad signal reception?

SOILWORK

Insulate the wires with heat shrink, you have to experiment with the placement of all the wiring. Like I said before servo glitching can be caused by the wires being to close to something electrical ar metal. Once you find a setup with no interference, secure the wires down so they dont move around when driving over rough terrain. This is a problem with a simple fix if it is your servo glitching.

derrick05

Did you cut the antenna wire?

RobertMP

Nope. I did not cut it. But it is very long compared to the plastic tube which is on the car. It hangs out as far as it can without any danger of getting in the wheels. The rest is folded in the battery casing.

derrick05

Try alkaline batteries in the remote and see what happens.You say you have 2500 rechargables.If they were new,on their first charge,then the batteries arent doing their job.It takes at least two charges to properly cycle new rechargable batteries.The first charge,straight out of the pack will provide you with less than half power.It isnt until you run that charge out and recharge, that you will start to see the real power of the batteries.

Hordsak

I wonder if having the antenna wire folded up in the box could be causing something. I would try un-folding the wire, and extend it fully out the tube. If it's really long, twist it around the tube.

The Real Dogman

Hey hordsak, you beat me to it, I just saw this thread last night and thought this morning. Well you are right if you have wad of wires that are powered you will naturally create Electro magnetic frequencies and your antenna being waded up in that mess it will pick up those frequencies.. So good call hardsak!!

Robert your antenna wire all the out of the tube let it hang down the antenna tube then slip a 1/4" peice of fuel tube over it to keep it under control.

Good luck!!!

rolland

I would also suggest using alkaline battery's in the TX. Rechargables have a lower voltage than regular alkalines it doesn't matter how many times you cycle them the voltage will always be lower.



rolland

RobertMP

I have an additional question, which I am not sure is related to my problems or a "feature"

When I give the throttle full speed and pull the brake fast, the servo just goes to neutral.
But if I relase the throttle and keep it at neutral for 0,5 seconds or more and then pull the brake it actually brakes.
I find that a bit odd and it often leaves me with a car that doesn't break when I want it to.

This is not related to the range between transmitter and reciever. This occurs even within cemtimers between transmitter and reciever.

dStruct714

Robert,

It sounds like your brakes aren't adjusted right maybe? Either that or your radio might have some weird settings in it. I'm not sure about the Magnum as I have a GST and Skyion DSX but when I'm going full throttle and I slam on the brakes, this damn thing stops on a freakin dime. If I adjust them any stronger it would flip itself over for sure.

Also I don't know about your manual but in mine that came with the GST it instructs you to turn on both radio and receiver and walk away from your car to check range, which might have helped diagnose your radio issues before it was fired up and running. You're lucky your car didn't take off on you..

Good luck!

RobertMP

Well thats where you are wrong. It did take off, but I was really lucky. It stopped in some really soft bushes.


I got some good advise I need to go test now.

Discharge new batteries and charge them again for more power (They are brand new)
Install alcaline batteries in the transmitter.
Try insulating the wires. (Will use a normal insulated wire and reuse the shielding. Thats going to be a challenge!)

If all that fails ill either get really [:@] or

The Real Dogman

Robert dont get [:@] or [:'(] We can help you, just be patient and very specific when describing your problem. We are here for ya buddy!!!

rolland

Rechargeable AA battery's have a voltage of 1.1 to 1.2 volts so if you are using 4 of these in the truck for the servos you are only operating the servo's at 4.8 volts max. Alkaline AA's are 1.5 volts apiece which will operate the sevo's at the recomended 6 volts.
This is the reason that rechargable hump packs have 5 cells, so the servo's can operate at 6 volts.




rolland

dStruct714

Yeah that's one of the first things I went out and got was an XTM 1000mah (1amp) 5-cell receiver pack and charger, if I had known better I would have got one of [link=http://www.rcplanet.com/ProductDetails.asp?ProductCode=VNR1501&click=3]these[/link] but oh well.. Just make sure if you have a "JST" (2-pin red connector) for your receiver pack your battery has one too, my LHS sold me one with a 3-pin connector and I had to return it.

burningpoo

How much of your antenna was in your box...hehe box, thanks dogman...reading your other post got my mind going...
Sounds like that might be your problem to me...I had to cut about 4 or 5 in off my tube to get my antenna trough even with using baby powder in the tube and on the wire...got about 6 in of wire hanging out of the top of the tube...came close to getting it ripped out when I rolled the truck for the first time...lost the black tip, now I’m going to try the fuel line or something close to that to help hold the antenna tube in place when I go a little to nuts...

When I was a kid...I saw a dude with a piece of clear body cut out...about 2x4 in, he had the wire running around the plastic in a spiral, from bottem to top, inside the body of his car. Told me that he got better reception. I've never tryed this trick...I'm not to sure I would recommend it, but if anyone feels brave...let me know how it works for you

dustin7837

My Feedback: (1)

Never tried it on a car, but I have done this on micro heli's rather than have a big antenna tube sticking out. I wouldnt say it gives better reception, but it seems to have about the same range as using an antenna tube (on the heli's anyway)

RobertMP

Finally some progress!!

I tried insulating the wires going from reciever to the 2 servoes. I used the metal wire insulation which is found on other wires and pulled it over the 2 wires. Wasn't very presise work. Just to test.

I immidiately saw change. When I turned on the car there was absolutely no sound (transmitter off). This doesn't usually happen and I normally hear the servoes twitching. But now complete silence.
At first I though the battery was disconnected, but once I turned the transmitter on the servoes went straight to neutral. (Small victory dance performed)

I then set up the car on a small podium so the wheels could turn freely and I started walking away from the car. I reached about double range of any previous attempt!
And the best part is when I started loosing connection I could hear the servoes twitching, but if I raised the antenna as high up in the air as I could the car behaved again!
It could never do that earlier. When I cost connection I often had to be within 1 meter between transmitter and reciever to get connection back. But not anymore!!
My range was about 25-30 meters and I hope the cause of that is the low voltage on the transmitter. The display reads 10.2V and I am using 2500mA rechargable batteries which are new and only charged once. I heard they will become better once discharged and charged again. (But others told me to use alcaline, since they have higher voltage)

Next stage!
So now ill create 2 new insulation wires for the 2 servo wires and try connecting those to the - on the battery, which should improve performance even more.
A very small modification and I should be up and running!

I imagined this hobby would involve loads of cleaning the little car and taking it apart, just to put it back together. I didn't thing I had to become an expert in electrical interferance!