PCM

[Mike229]

I have a rd 8000 transmitter, butt the manuel is very vague on PCM what does it mean and waht does it do?? Do you need a speacial crystal for transmitter and reciver for PCM

[antsis]

Mike

PCM stands for Pulse Code Modulation. Basically, the signal is sent to the receiver in digital format. Similar to the way computers communicate. In PPM, the signal is sent as a radio wave and the receiver works much the same as your standard FM radio. PCM is preferred as it is usually less susceptible to outside interference.

You don't need a special crystal, but you have to use a PCM receiver. These are obviously more expensive compared to the PPM ones.

[Ade_Law]

you can also setup a fail safe on PCM. when the signal is lost the reciver sets the servos to a preset position. this is not to stop a crash but to stop the model from flying away or doing damage to people/property

The main thing is that the throttle is set to idle/stop.

this prevents the model flying away and also reduces the energy in the model when it does hit the ground.

Ade