now from my limited knowledge what i know that a module radio such as the futaba 9C allows you to change frequencies....compared to having one set in stone unless you send it to them with the 7C...now where i plan to fly is VERY busy (Markham park in ft. lauderdale)...so wouldnt i be better off w/ the module?

what other benefits does it have?

what other benefits does the 9C have that the 7C doesnt?

just want to know if its worth the extra $100.

Edit: if this belongs in the radio forum (thought i was there) can someone please move it?

Thanks

Chad

If you plan to fly in a busy area, definitely get a radio with a module. Futaba is supposed to come out with a synthesized module for the 9C one of these days, and then you can tune any freq in the 72MHz band by turning a dial. I don't know all of the differences between the two... I have a 9C, and I helped a friend program his 7C. The 9C has a much better LCD display and a menus, and has a graphical display for heli throttle/pitch curves and for expo adjustments.

You might want to consider Hitec TXs... Hitec has a synth module out already for their radios. If you can get away with a 6ch computer TX, the Optic-6 looks like a good buy to me (see link below)... I'm considering it over the 7C for a second radio... no module in the 7C is a big turn-off for me.

http://www.servocity.com/html/6-ch_optic_6_systems.html

I used to have a Hitec Eclipse. 7 channel radio that had the module. You could change it to any channel from 11 to 60 and, use either positive or negative shift. So, any brand of rx that you bought and any xtal, you could use (not pcm however). I sold mine because I didn't really need to change the channels. And, the Eclipse only had a 7 model memory. I have a Futaba 9C radio that has unlimited
model memories because it uses a memory card. Therefore you could have 2000 models with their setups all saved on mem cards.
I currently use 4 transmitters, a park zone one for my F-27 Stryker, a Hitec Flash 5, Hitec 3 channel AM and my Futaba 9C.
The Futaba 9C uses a module just like the Hitec Eclipse. Matter of fact, they are interchangable as I've used the hitec module in my 9C.
One thing to note....if you get a futaba that uses the memory module, a Berg 5 and 6 channel DSP RX will not work with a futaba module. However, the hitec one works fine. Must be something in the futaba circuit board that the Berg don't understand. A Berg 4 channel microstamp rx does however work great though.

Dave...

I've heard it does work, but it's illegal to use the Hitec Module in the Futaba, according to the FCC...
I think you meant to say frequency module here...

Chad

You will most likely be better off with a 9C Super. There are limited quantities of these available that have the Synth module. These units work very well.

Just be aware that there are quite a few aftermarket receivers that will not work if you use a synth TX module. There are even some older Futaba PCM RX's that need to be upgraded to work.

Also, it is illegal and risky to use the Hitec synth TX module in any other brand TX.

The 9C is a very nice radio - I had one until I upgraded to a 9Z with a synth module - what a pleasure!

Safe Flying!

blikseme300

what does the 9C Super offer that the regular 9c doesnt?

i was looking at this radio specifically.

http://www2.towerhobbies.com/cgi-bin...I=LXASY0**&P=7

but it says FM...does that mean it will only work w/ crystal recievers? or just that i would have to buy a synthsized PCM reciever?...[]

also heres the "Super"

http://www2.towerhobbies.com/cgi-bin...I=LXHKS5**&P=7 w/ 4 digi servos. but again what does "FM" mean...can i buy a PCM reciever later down the road so i can change frequencies? or am i stuck?

hope you can explain...

Thanks

Chad

The 9C will transmit in both PPM (commonly just called "FM", even though PCM and PPM are both FM) and PCM. These two modes are unrelated to synthesized or crystal TX modules and receivers. If you buy a 9C with a crystal TX module, you can use any negative shift PPM RX with it, and a Futaba PCM RX with it (PCM is different among brands, but PPM is not). If you get a 9C with a frequency synthesized module, I've heard that some other brands of PPM RXs may not work with it, and of course, only Futaba PCM RXs will work with it. IMO, this isn't an issue, as long as you don't currently have a non compatible RX... there's plenty of PPM RX brands out there that will work just fine with it.

The 9C is a great radio, I have the 9CHP, which is the heli version that comes with a PCM RX. I fly a PCM RX in my Heli and in one of my planes, and PPM RXs in all the rest (Hobbico and Hitec brand PPM RXs). If you have the $$$ to shell out for a 9C, I think you'll be very pleased with it... I know I am!

Oh... and the "Super" version is just the latest version, with updated software... read the description in that Tower link that you posted, it tells you what enhancements the 9C Super has over the original 9C... you can decide if it's worth another $50 or so to you...

alright from what i got from that if i want to use a syntheized reciever i have to buy a PCM radio?...


btw -pkh- do you happen to have AIM? if you do i'd like to talk to you a bit more about this radio stuff...

hit me up at chdwik88.

Thanks

Chad

Nope, you still don't ahve it right.

There are synthesized receivers and there are synthesized modules for transmitters/radios. They are two entirely different things.
PCM is neither. PCM is a method of coding informaiton on an FM transmission. A PCM receiver needs the radio to transmit in PCM code.

This has nothing to do with whether the receiver or the transmitter are using a synth.

These articles might be helpful.

Radio Systems Part 1 - Standard Radios
http://www.rcezine.com/cms/article.php?cat=&id=44

Radio Systems Part 2 - Computer Radios - A Better Investment
http://www.rcezine.com/cms/article.php?cat=&id=65

ok ok lets try one more time....lol

oh and for anyone who says this stuff isn't confusing... is a liar (at least for a beg.)

now no matter if i buy an FM (PPM) or PCM tx it will use a normal cystal reciever unless i buy a synthesized module?

so that means i can go ahead and buy the PPM 9C w/ 4 servos and latter i an buy the synthesized recivever so i dont have to deal w/ crystals in case i need to change frequencies?...PLEASE say this is right....

Thanks

Chad

Chad,

I don't have AIM, but you can PM me if you want.

The 9C does PPM and PCM, regardless of whether you get a crystal module or synth module for it. The receiver doesn't care which module the TX is using. If you get a PPM RX, you need to put the 9C in PPM mode... if you get a PCM RX, you need to put the 9C in PCM mode. I have both PCM and PPM RXs in my RC aircraft, and fly them all with my 9C.

Like you said, let's try this one more time...

1) PPM and PCM are two different modes of FM transmission. The 9C can transmit in both modes.
2) If a TX or RX is "synthesized", this means it does not rely on a crystal to determine the channel it is tuned to, and it can electronically tune any channel within the band.
3) If a TX or RX uses a crystal (or a module with a crystal), this means it relies on that crystal to determine it's channel, and you cannot change the channel without changing that crystal (or the module with the crystal).

So PPM and PCM are two different types of FM transmission, and synthesis and crystals are two different ways to select a particular radio channel. The mode (PCM or PPM) of the RX and TX must match up for them to work together. The way the RX and TX tune their channel (synth or xtal) does not have to match up, they just must be tuned to the same channel.

To completely rid yourself of having to buy xtals, you need a synth TX and a synth RX.

1) right I understand the basics of PPM and PCM and that they are both FM...now if the 9C can do both then why is the PCM version more? (w/ the same servo's etc.)? its an extra $40 for the FM compared to PCM versions...
2) so that means you have to buy the tx as a synthesized...such as this. http://www2.towerhobbies.com/cgi-bin...?&I=LXJDG0&P=7 ? $500 is just a bit much....no servos either.
3) understand this...you have to send it to futaba to change it...

right?

Thanks

Chad

There is no PCM or PPM version of the 9C transmitter... just one version that does both modes... Futaba confuses things with the way they name the TX/RX/Servo bundled packages...

The aircraft version of the 9C TX says 9CAP on the front of it, and the heli version says 9CHP on the front, regardless of whether you get it bundled with a PPM or PCM receiver. If you buy TX packaged with an PPM(FM) receiver included with it, Futaba calls it a 9CAF or 9CHF, but the radio will still say 9CAP or 9CHP on the front!

A crystal module for the 9C is $49, and the synth module for it is priced at $89 right now, according to Tower (it's not released yet). So you can obviously expect to pay more for the synth version...

Since the 9C TX takes modules, you don't have to send it into Futaba to be retuned to another channel... you just buy another freq module... $49 for a single channel crystal module, or $89 for the synth module that can tune all of the 72MHz band channels. For example... I bought my 9C with a ch37 module, and subsequently bought a ch49 module for it (since another regular guy at my club already had ch37). I can now use either channel module in my 9C TX to tune ch37 or ch49, as long as I have a compatible ch37 and ch49 xtal for the RX I plan to use with it.

damn futaba...making it all the more confusing on me...[:@]

ok so now that i understand that their is only one type of 9C transmitter....

so if i buy this one... http://www2.towerhobbies.com/cgi-bin...I=LXHKS5**&P=0

it uses a a crystal module that is set to one channel correct?...

like you said you would have to buy the $89 synth module and a synth reciever? such as this? http://www2.towerhobbies.com/cgi-bin...I=LXHUP0&P=ML?

and if their are no differences between the supposedly same FM and PCM transmitter why the $40 difference?

Thanks

Chad

Yes, that Tx comes with a single frequency module. You could change the Frequency by replacing the single frequency module with another on a different channel.

No, you do not have to use a synth Rx to pair up with a Tx using a synth or single frequency module. If you had only a Tx with a synth module but a normal crystal controlled Rx the procedure for you to change channels is to dial in the new channel on the Tx synth module and to change the crystal in the conventional Rx with a new crystal to to the new desired channel. It is not illegal to change your own Rx crystals.

The forty dollar differance in the that radio as pkh noted is due to packageing. The PCM package is more because it includes a PCM Rx instead of a FM(PPM) Rx which is much more expensive. Just look at the prices of FM and PCM Rx's. The Rx is where the difference is.
Also this kind of packageing is common to most radio systems and not just Futaba.

John

You have to read what the entire package includes with the TX... look at the RX that comes with it, the type of servos that come with it, and the capacity of the RX batt the comes with it... PCM RXs are more expensive, high torque servos are more expensive, and the synth module is more expensive, high cap RX batt is more expensive, etc. Different radio packages bundle together different RX/Servos/batts, and the price will vary depending on the value of the included stuff.

Also, the 9C "Super" will likely be a little more $$$ than the old, discontinued 9C. Here you're paying to have the latest/greatest firmware in the TX.

I'm am considering purchasing a 9C and this thread has been EXTREMELY helpful in explaining the difference between Futaba's 9CAP vs. 9CAF designations. Thank you guys for being so patient, explaining it until everyone understands!!!

I have the 9C as well....and I was Sooooo confused trying to figure it all out before I bought mine........


but I LOVE my 9C!

If all else fails, go to the Futaba web site and download the manuals and do some reading. It will take a while but you will/should/might actually learn?
I vote for the 9c with synthesizer BTW.

One more thing that wasn't mentioned yet is you can take the same 9C and drop in a 75MHz module and use it for cars/boats/robots. You will need to get a RX on 75MHz, as THE 72MHz RX CANNOT BE USED WITH THE 75MHz TRANSMITTER WITHOUT HAVING IT RETUNED. I'm getting one on 75MHz for my boats and getting a 72MHz synth module and RX later for the aircraft I'm working on. This lets me use one TX for everything, much cheaper than buying complete new radio sets for each new project.

he will get more confused when start looking at words such as mixing, dual/triple rate, flaperon, elevon etc. but it will be a great & nice radio to invest to.