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Old Apr 28, 2012, 10:38 PM
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United States, KY, Paducah
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Pcm/ppm ?

First off, I don't really know about how transmitters and receivers work entirely - I guess if I did I wouldn't ask probably such a simple and beginner question . . . .

So you may already know from another thread of mine that I'm looking to upgrade to a better transmitter. My question is: If I get a transmitter that uses PCM or PPM, will it work with any standard 72mhz receiver? Or If I have a tx that uses PCM do I have to have a PCM rx and/or If I have a PPM tx do I have to use a PPM rx?

Like I said, I don't really understand all of the frequency waves and how the radio transmits it so this may not make any sense

Thanks,
Nicholas
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Old Apr 28, 2012, 11:51 PM
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Originally Posted by PyroMan View Post
First off, I don't really know about how transmitters and receivers work entirely - I guess if I did I wouldn't ask probably such a simple and beginner question . . . .So you may already know from another thread of mine that I'm looking to upgrade to a better transmitter. My question is: If I get a transmitter that uses PCM or PPM, will it work with any standard 72mhz receiver? Or If I have a tx that uses PCM do I have to have a PCM rx and/or If I have a PPM tx do I have to use a PPM rx?
Like I said, I don't really understand all of the frequency waves and how the radio transmits it so this may not make any sense Thanks, Nicholas
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Old Apr 29, 2012, 02:59 AM
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Transmitter and receiver modulation method (PPM/PCM) must match. If you are going with 72 mhz FM, I would say the majority of new micro receivers are PPM (pulse position modulation). You may want to look at 2.4G technology as you upgrade, as this appears to be the current state of the art. However, 72 mhz FM still works very well, is available at very reasonable prices as people migrate to 2.4G, and is becoming increasingly interference-free as the 72 mhz channels are abandoned.
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Old Apr 29, 2012, 04:00 AM
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Originally Posted by whitecrest View Post
Transmitter and receiver modulation method (PPM/PCM) must match. If you are going with 72 mhz FM, I would say the majority of new micro receivers are PPM (pulse position modulation). You may want to look at 2.4G technology as you upgrade, as this appears to be the current state of the art. However, 72 mhz FM still works very well, is available at very reasonable prices as people migrate to 2.4G, and is becoming increasingly interference-free as the 72 mhz channels are abandoned.
You're correct. But........ For you guys. I would for example I bought Futaba 9cap super. I would convert like I did to either to Wfly module or Frsky. Receiver are cheap and you get the 2.4ghz technology. No interference. Yes since people are moving up to 2.4 there is less interference now with fm no matter you're fm or fm pcm since now there is only few on FM.
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Old Apr 29, 2012, 08:38 AM
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Okay, so is PPM like the standard way of transmitting? What I mean is, does the standard, rub-of-the-mill transmitter use PPM?

For the record that is my plan, get a relatively nice 72mhz transmitter and then upgrade it to 2.4ghz. My plan is to do what I saw a guy do on YouTube, have both a 72mhz and 2.4ghz board in the rx and have a switch to switch between frequencies. Im thinking about getting a JR 7202 or a JR 8103 - I'm leaning toward the 7202 because it ha 20 model memory and comes synthesized so I don't have to buy a new module.
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Old Apr 29, 2012, 12:01 PM
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Forget 72 and go straight to 2.4. Don't waste time and money along the way. You will end up with 2.4 anyway.

One good way is to get a module type transmitter such as JR 8103 or XP9303 and an FrSky plug in module. Another is to use the FRSky hack module in 7202 or similar.
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Old Apr 29, 2012, 02:08 PM
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My plan is to go one of two ways . . . Buy a modular 72mhz radio with a synthesized 72mhz module and also buy a 2.4ghz module so I can fly on any 72mhz channel and on 2.4ghz depending on the plane.
My other way is to buy a radio like the 7202, where it is built with a synthesized system and then do the hack module. I want to be able to fly on 72mhz on most any aircraft channel and on 2.4ghz with the same radio.

So yeah, I will be going to 2.4, but I'll will get there by means of a hack module or a snap in module like you said.
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Old Apr 29, 2012, 03:14 PM
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Originally Posted by PyroMan View Post
My plan is to go one of two ways . . . Buy a modular 72mhz radio with a synthesized 72mhz module and also buy a 2.4ghz module so I can fly on any 72mhz channel and on 2.4ghz depending on the plane.
My other way is to buy a radio like the 7202, where it is built with a synthesized system and then do the hack module. I want to be able to fly on 72mhz on most any aircraft channel and on 2.4ghz with the same radio.

So yeah, I will be going to 2.4, but I'll will get there by means of a hack module or a snap in module like you said.
Unless you have a specific need for 72 (such as for FPV use to avoid conflict with the video transmitter) there is no point in spending any significant money on 72 equipment. On the other hand, if you can get it really cheap, it might be a useful interim step.
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Old Apr 29, 2012, 04:12 PM
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The main reason I am going to get a 72mhz radio is because all of my planes are on 72mhz, and if I spend money on a 2.4ghz radio, I won't have the money to buy all new receivers for all of them. Even if they are relatively cheap . . .
So if I can spend some money on a quality radio that I can use on my current planes and can upgrade in the future, then I'm going to do that
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Old Apr 29, 2012, 06:34 PM
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Quincy IL
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Most important thing in the decision process first

What brand of 72 MHz receivers do you have?

I have an XP9303 and two PCM 10X JR TX's. Have 72KHZ synth modules, a spectrum module, FrSky module a mix of planes & receivers. Works well for me.

Really like the telemetry system for the FrSky, very similar to my Aurora 9.
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Old Apr 29, 2012, 08:36 PM
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I have a JR R700 and a few +/- shift Corona receivers.
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