My new plane fails its radio range test (with or without the engine running) I have set up several planes with success but this one is giving me trouble.
The plane is a Pheonix laser,The radio is Futaba 6EXAS. The receiver is a Futaba R127DF with 54 crystal, battery is Hydramax 6.0 V Nimh (fully charged). Servos are Hitec 635s. Radio (with the antenna down) cannot be moved past 15 paces and the servos twitch. I changed out the receiver with another, both worked fine in other setups. Same result. I moved the receiver antenna so it was hanging out of the plane completely, no range change.
The only thing different from my other setups is going to a 6.0 V battery. Can this model of receiver handle the 6.0 volts? The servos are supposed to. Or is there something else that can cause the servos to twitch. Does anyone have any thoughts that might help me?

what is the battery voltage with a loaded meter? is the antenna touching a lead from the battery or the switch? if all else fails try another battery

6V batteries can cause "jitters" when the battery is at peak charge. You might want to add a 6V or 5.2V voltage regulator to cap the maximum voltage going to the receiver. This will remove the jitters caused from peak voltage and still provide the fast response times and extra torque that 6V batteries give you.

I use the futaba rx that you have with my 6v battery. In fact all of my planes are setup with 6v and have not experienced any problem. Some times when I do a range check and my plane is near my truck then I get the same problem that you are experiencing. I just have to move the plane. What did your battery peak out to?

Often, you can get servo twitch with a fully charged battery, especially with a 6 volt pack.

Try using a 4.8 volt pack and see if you still get the twitching. If that doesn't work, then play with the antenna location. Make sure that the RX antenna is straight and fully extended, and that it is no where near any metal, such as all metal pushrods.

CGr

Assuming that is not an electric airplane, start by checking all the servo leads are plugged in correctly. If good, then unplug ALL servos and plug a known good servo into the receiver and then do the range check. If it checks good, then start plugging in existing servos one at a time and range check each additional servo.

Happy Landings?

Have you tried a 4.8 volt Rx pack ?


Bob

i'll try a 4.8 volt battery and if the twitch goes away i'll purchase a voltage reg. to control the excess voltage, The servos repond fast at 6.0 V. i also had a friend tell me that control rod binding can cause a twitch. That doesn;'t seem likely as all the servos are jumping like frogs at 15 paces. I ran the voltage down to 6.3V and still had the problem. I am going to help my friend with his vinyl siding project this weekend, but will get back to the forum on Monday. Thankyou to all. Groundkeeper3404

I have some JR analog servos that jump around if I peak the battery then turn on the plane right away. None of my Futaba or Hitec servos do that unless I'm range checking and the plane is next to A chain link fence, that has happened A few times.

A new chain link fence was istalled at the airfield I tested the plane at. Will try a different location. Thanks

I was told to range check with the antenna on the tx up one section. Futaba recommends this with the 9Z 12Z and 14Z radios. I'm not telling you to check that way. I was told that by an experienced flier in my opinion and I have never lost a model due to radio problems. Except when I flew away with my antenna down but that's another story.

The 1 segment up for range test applied only to very specific Futaba radios (maybe others too). The antenna's were in a shielded sleeve inside the case (or the case was metal) and thus couldn't transmit when fully retracted.

On any other radio, this would lead to a falsely re-assuring range test, as even a single section out grossly increases transmitted power.

J

I always try to keep the antenna at least 2 inches away from any servo lead or battery lead. It does sound like you have one servo that is the culprit tho.

I installed a different receiver, battery & switch. Plane passed the range check. I taxied around the strip a couple times. Took off brought the plane around twice. Was in the trim process and the plane took off and disappeared over the cedar trees. Something still wasn't right. Life goes on. I really liked the way the Pheonix Laser flew, although it was a short flight. It was a well built plane but ARFs dont take a hit to the ground very well. I'll do it all over as soon as I receive another ARF. And win the lottery. I hope the manufacturer's warranty on the plane is still good. HA HA
Thanks to all who added input.
I'm going to take my trainer out to the field and get back on the horse I was kicked off of.