Ferrite rings are useful to reduce electromagnetic interferences at servo patch cables connected from the receiver and to motors.
In case you have interferences at one of following modules:
Sound module USM-RC-2
Speed controller UFR-1230
IR light module SM-IR-16-2
you can use ferite rings.
Remark for IR light module SM-IR-16-2:
When controlling trailer supports with the light module it is important to suppress electromagnetic interferences at the reveiver diode as well as at the motor cable.
The cable should be wrapped 4 - 5 times arround the ring for a good suppression.
Size ferrite ring:
Outside diameter: 16,0 mm
Inside diameter: 9,6 mm
Height: 6,3 mm
Core material quality: T38
Weight: 4 g