I'm radio shopping, debating between a new 7 or 9 channel Futaba. Short question: Will a PCM transmitter work with FM receivers? I have several chipsets already in my favorite channels, so whatever I buy I'd want to be sure it's compatible with what I already have. Thanks.

Mike/Rob,

The only difference between PCM and FM is the receiver. You will be able set the tranmitter to transmit in either the PCM or PPM mode. PPM = FM. The standard
receiver included with the radio should be a FM or PPM receiver. In PPM mode, it
is more easy to notice glitches (radio interference). It PCM mode, most glitches are masked.

Hope the above helps.

Hi Mike,

Rob is correct in what he says.

Both the seven & nine channel radio systems, the transmitter is same in the PCM and FM versions. They are selectible between PCM and PPM (FM) modulation.

The difference in the boxes will be the receiver will be either PCM or PPM (FM) and could be different servos or no servos.

So yes...Whichever one you get, it will work your current Fubaba or Futaba compatible reveivers when you set up the model memory for that particular receiver and specify PCM or PPM modulation in the model memory.

Now, about the chipsets.
I don't know if the Transmitter crystal in your old crystal sets will work with the new type transmitter. I think the new transmitter will have a swapable frequency module that you change out and not just do a crystal swap.

Best thing to do, would be to get new crystals for your old receivers to match whatever frequency your new transmitter is on.

I think that you can get a "Selectable Frequency Module" for that transmitter and you can dial in any transmitter frequency that you want at any time for a particular receiver.
Something to look into.

Good luck on makeing any sense out of what all I said above.
Done confussed myself. :unsure:

ARG!! :pirate:

Alright great, thanks guys. What I'd most likely do is order the new radio in the frequency I already have.

Next question. And I know I already know the answer to this one, but I'm going to ask anyway. A helicopter radio can do everything an airplane one can and more, right? So if I'll eventually have one of these fancy helos, getting a helicopter radio now wouldn't be a bad idea?

Oh, one last question. What would 9 channels actually be used for? I can think of the 6 most common, but can't imagine what having 3 more would do for me. Thanks again guys.

Mike,

The airplane and helicopter versions come with the same software in transmitter.
Difference being, the helicopter transmitter switches are arranged and labeled for helicopter mix functions. Either one will fly airplanes or helicopters the same.
There could be a difference in what comes in the box with the helicopter version. Like maybe five servos or little better servos or a larger flight battery pac. Something to check out.
So I would say if you plan to fly mostly airplanes, get the airplane version or if you figure to get mostly into helicopters, get the helicopter version.

Channels:
For a helicopter.
Five channels used for primary flight functions. Roll, Pitch, Yaw, Throttle, and Collective Pitch.
Sixth channel used for control of gyro.
Seventh channel used for Main Rotor Speed Governor control.

There you have used the seven channels and if you wanted to do anything else, like retracts, remote controlled engine needle valve, turn on lights, drop bomb, and who knows what, you would be out of channels.

Airplanes are less channel intensive I think.

Bottom Line:
Seven channels are probably all you will ever need, but if not that much difference in price then go for the nine channel radio. They say to spend the money on best radio you can talk yourself into and you will not have to rebuy again too soon.

I have the airplane radio and it gets my heli around just fine ;) I will be going to the heli radio soon. Now that i fly more helis than planes. So alvin is right both will do them just fine if it is any of the futaba 9c radios.

Excellent, excellent information gents. Thanks. I decided to go with the 7CAP. For what I have now, and what I expect to have in the next couple of years, it's all I'll need. One day, if I can actually afford something that will need to utilize 9 channels, affording the radio won't be a problem either. :lol: