Model Forum / Radio Controlled / Air Models / February 2004

On 2/19/2004 9:46 AM Ted shuffled out of his cave and grunted these
great (and sometimes not so great) words of knowledge:

1st, are the transmitter and receiver compatible ? (HiTec/Futaba, etc).
2nd, is the receiver battery fully charged ?
3rd, replace one of the servos with a known good servo and see if it
still "jitters".

If the first 2 are ok and the good servo still "jitters", check the
battery for a possible bad cell (cycle it a couple of times and see if
the readings are similar to a known GOOD pack of the same size).  If the
battery is good, check the connections at the switch and receiver for
corrosion/oxidation, especially if the good servo doesn't "jitter".

This is probably a silly question, but are you sure you have the right
frequency and right type (single/double conversion) crystal in the receiver?

Regards, Kevin

I recently got a used R/C plane, and the the servo's start to move (all four
of them) when the transmitter is turned on.
They all move at the same time on their own without anyone touching the
transmitter. Now its not the transmitter, because I use the same one and
frequency  for another plane.

Anyone have any ideas as to why they may be doing this? Bad receiver? or bad
servo's? or something else?
Thanks for any help!

Hi Rick

I have experienced this and after a trip back to the manufacturers for checking turned out to be the new R/x crystal was off frequency.

FMA receiver and FMA supplied crystal.

Vic Shaw
P.S.: Maybe we're related.

 I recently got a used R/C plane, and the the servo's start to move (all four of them) when the transmitter is turned on.
 They all move at the same time on their own without anyone touching the transmitter. Now its not the transmitter, because I use the same one and frequency  for another plane.

 Anyone have any ideas as to why they may be doing this? Bad receiver? or bad servo's? or something else?
 Thanks for any help!

 --
 http://home.fuse.net/rickshaw/

If this is happening in the house it is quite likely normal due to reflections etc.  Take it outside and do a proper range check and see if they are still twitching.
Gord Schindler
MAAC6694

 I recently got a used R/C plane, and the the servo's start to move (all four of them) when the transmitter is turned on.
 They all move at the same time on their own without anyone touching the transmitter. Now its not the transmitter, because I use the same one and frequency  for another plane.

 Anyone have any ideas as to why they may be doing this? Bad receiver? or bad servo's? or something else?
 Thanks for any help!

 --
 http://home.fuse.net/rickshaw/