rekim

iTrader: (7)

how come people recommend 4 channel remotes.

I only ever use 2, but it seems people recommend the 4 channel remotes like the dx4s

what are the other 2 channels used for?

Roelof

They are actually used voor surface (car/boat) purpose.

A 3rd channel is normally used for a mix like 4 wheel steering, 4 wheel brake or a tilt with a boat outboard motor. But it can also be used for a gearbox reverse switch as used on several Traxxas models and the HPI Savage.

Now with AVC an extra channel is needed to control the gyro.

TeamSkunkwerks

iTrader: (142)

Sometimes people run the extra outputs to power other items.
Servo for steering
Throttle servo or ESC
Glitch Buster
Transponder
Motor Temp probe or battery temp probe

Just depends on your setup & what you might be running.

Salkin

Because some of the best radios have 4 channels. People don't recommend them because of the number of channels, but because they are good radios.

Roelof

That has nothing to do with a transmitter of 3 or 4 channels. Even most dedicated 2 channel radio's today do come with 3 or 4 channel receivers.

Myt3rocks

This. The good radios come with more channels. Most don't use them, but it's hard to sell a high end radio with less channels.

Salkin

On a side note, the left over channels are in many cases used to power e.g. a motor fan and a transponder.

In our case, we race touring car, use the M12, the receiver has an extra "power" channel, so 5 in total, but we need two extra channels to power the motor fan and the transponder, leaving only one not used.

If we used a 2 channel receiver, even one with an extra "power" channel, we would be one channel short.

kawi650

iTrader: (8)

Salkin is dead on, the best ones have at least 4 channels these days. 6 channels may be the new normal if the DX6R is an indication of things to come.

I have a crawler that uses 5 channels: steering, throttle, shifting servo, winch, and light switch. Rarely in racing will you use more than 2 but there is much more to the RC world than the small corner of racing.

sakadachi

iTrader: (1)

I use the open channels for sensors to trigger lights on my crawlers. Also to run fans on ESC's that did not come with fan wiring. Glitch buster capacitors, etc. If you're racing you'd probably use the open channels to power your transponder.