savke

My Feedback: (36)

Hi!
I have maybe a dumb question but since i am new in this hobby i have to consult somebody.So please guys help me
I would like to buy Futaba radio system.It comes with Tx and Rx. The guy in the hobby shop says it is PCM .But it says PCM only on the transmitter.On the receiver it saya dual conversion.Here at the message board i saw that guys who are selling their old radios have PCM sign written on both Receiver and Tranmiter.
So please can somebody help me about this thing.
What dual conversion means?

dbow

My Feedback: (1)

I have the Futaba 3PJ (PCM) 3PDF (No PCM) and the 6XAS (PCM capable)

Pay attention to the last radio I mentioned, notice how I specifiy that it is PCM capable. THis radio comes with a standard rcvr, while the radio will function in the PCM mode it will not with the rcvr it comes with. You would have to buy another rcvr in order to operate the radio in PCM mode.
That may or may not be the case with the radio you are looking at. The rcvr will say PCM on it, I think its "PCM 1024" on the front of the rcvr. I think all futaba PCM rcvr are stamped this way.
If it does not have it then its not PCM.

Dual conversion means the signal is filtered twice.

Dbow

Bonefrost

My Feedback: (6)

My PCM radio has a PCM reciever.FM would probably be better.PCM recievers and crystal sets are more expensive.I'm using AM because it's alot cheaper.
BNZ'

tylern

if you are flying in the air there is high band.and on the ground that is low band,now the radio you need is 27.mhz.and in the air is 72.mhz. you be sure you dont put a air receiver in a car.or a car rec.in a plane.if you put a air in a car and turn it on you could mess up a plane some were that you cant see.cars only reach out a little way but plane rec will go a long ways.you can run a plane so far away you cant see it.you must never go so high up were you are in the clouds you can hit a real plane or maby more, but all in all 27.mhz and see if there is a set or #s on the radio and rec must be the same.the crystals in all air boat truck car.any thing that has a radio will havea crystal.also see if it is am or fm. if you need more ask

transmission_dr

My Feedback: (1)

You can go here http://www.futaba-rc.com/ and check the receiver number, that will tell you exactly what the shop is trying to sell you.

Futaba PCM receiver numbers end in P, e.g. R148DP is an 8 channel PCM receiver, R148DF is an 8 channel FM receiver.

Futaba sells radio systems with a transmitter that can select either FM or PCM operation, but the receiver will be either FM or PCM not both. PCM receivers are significantly more expensive so a PCM system is more expensive. To operate PCM both the receiver and the transmistter must be PCM.

If you are running or plan to run gasoline ignition engines then I would strongly reccomend going with a PCM receiver, otherwise FM is fine.

72 MHZ channels are aircraft frequencies, 75 MHZ channels are ground frequencies, 27 MHZ can be used for either air or ground, but you would have to be foolish to operate aircraft on 27 MHZ because of the CB interference.

Hope this clarifies things somewhat.

Jerry

dg2b

I would stay away from 27mhz period. This band is shared and FCC is trying to reclaim its use outside of RC.

Do you guys know if 41mhz is legal in US and/or needing a HAM license?

transmission_dr

My Feedback: (1)

So far as I know 41 MHZ is NOT legal in the US. You can operate on 50 MHZ (6 meter ham band), but you need a ham license to do so.

Jerry

dg2b

Thanks Jerry. I keep seeing ebay auctions for 41mhz. Would be nice if it was useable.