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Transmitter help

#1
For airplane what is the max number of switches you will ever use? Reason I ask is because I was going to get the qx7s and I had problems with a website so I was looking else where and saw the 9xd is about the Same price and saw they came out with the 9xd special. And don't know if I would ever need that many switches on the 9xd and the qx7s would work. But if I think I would use that many switch I would go with the 9xd special.
Thanks happy flying
 
#2
I have one plane I have set up that uses every switch on a 9xd but I may have gone a little crazy (especially as I have a hard time remembering what each switch does). It was for a glider that I set up every possible mode you can think of on a glider that only has 7 channels (2 ailerons, 2 flaps, rudder, elevator, and throttle). Even I question if what I did really makes sense and if I should simplify that plane.

If I had to guess, for 99% of people (especially on this forum), the QX7 has enough controls for you. If you need more (not like me going crazy just because I can), you are probably flying a plane that is significantly more expensive than any version of the Taranis radio (like an actual jet or a high end competition carbon fiber motor glider) in which case you probably can afford to upgrade to a FrSky Horus or other high end radio.
 

rfd

AMA 51668
#3
aiy yiy yi, muchacho! i doan need no steenkin switchees!

well, maybe one or two, now and then. for that matter, 6 channels is rarely needed as well, mostly 3 or 4 is all that i'll need and ymmv.

a qx7 with the irx4 module is a sweet tx. and it appears the jumper t8sg might be as well.

assess yer modeling flight needs and get a tx with the controls to administer those needs.
 
#4
It really, honestly, depends on what you'll need. My dad has a Spektrum DX7 because he wants to have the ability to use flaps on his sailplanes, and the ability to use telemetry.

I'm going to 3D print a P-38 Lightning from the 3DLabPrint guys, and with that, I'll need a minimum of 6 channels (Throttle, ailerons, rudder, elevator, flaps, and retractable gears). If I wanted to throw in dual ailerons rather than using a Y-connector, I'd need a 7 channel transmitter.

Will you use a ton of switches? Most likely, no. I find I use, at most, 3 switches. I have a throttle kill switch (something my field requires I have in use for everything I fly, with the exception of sailplanes that have no motor), a switch for various levels of expo, and a switch to turn on mixing for my differential thrust on my Sea Duck. I suppose if I had another twin motor plane that I wanted to set up differential thrust AND have retractable landing gear, I might use more than 3 switches, but honestly, it's kinda rare.

I'd recommend planning for at LEAST a 6 channel radio; while you technically can get by on 4 for most planes, you'll find that you need at least one dedicated channel for that throttle cut, and having another channel for changing flight modes is a bonus for drones. I'd say that it really depends on what you plan to fly; if you think you're going to get into helis and intricate gliders and wanting to open a bomb bay door while retracting landing gear, it might be to the benefit of purchasing a higher channel radio.
 
#5
If you are planning to be on the forums here and potentially get into some of the more challenging build or some of the competitions switches are cool. Having them and not needing them is one thing. not having them and needing to get another radio down the line gets expensive.

I am working on just a video system for one of the current build projects as a secondary flight crew and I am using 8 channels. Not including what is needed for the pilot to actually fly the plane. 4 channels for pan and tilt on two separate cameras, another servo for tilting the cockpit camera to become a bomb drop sight, one for camera switching for FPV, one for bomb bay doors and the last for bomb drop.

Everyday use more then likely 6 channels is most you will use regularly but its that one time you want more you will kick yourself for not planning ahead.
 
#6
I would go for more switches and channels if the price is about the same. I started with a DX6 Gen 2 after only 2 years I upgraded to a DX9 Gen 2 ran out of channels and switches. If you ever think about adding a stability system in an airplane Eagle Tree, telemetry, and doing flaps, ailerons, dual servos on elevator, rudder, and retracts 6 channels is not enough. The new Eagle Tree with 6 axis and 6 flight modes eats up either 2 switches or 3. As Bitorg said if you ever decide to fly sailplanes and do it really right you will NEED switches, and sliders are great to have ..
 

rfd

AMA 51668
#7
going with open-tx (taranis, jumper, etc) yields 8 channels at least and a gaggle of switches and dials. that's faaaar more than any newbie needs from the get-go, with lots of future bells 'n' whistles on tap if need be. and the price tags will be lots less to boot.
 
#8
With the 9xd special with the unscrewedable anntana I heard you don't want to keep putting it on and off or the connection will get bad is this true if so could you modify the case that it comes in. to fit the 9xd with the anntana on?
Thanks
 

JimCR120

Site Moderator
#9
You're likely the best one to determine how many switches. Consider throttle, ailerons, elevators, and rudder. If you want lights, gear, or flaps those all would take a channel each as well as any other special device. That said, as much as those options sound appealing, I don't have anything that uses all of them nor much that goes beyond 4 channels. I have an Excalibur that is normally a basic 4 channels flyer but I put each aileron on its own channel which gave me the option for flatperons. Cost vs benefit... you get to choose whether what you buy will be utilized enough to justify the expense.
 
#10
The X9D and Q7 have a big price difference. Are you comparing transmitters with the same type of gimbals and case included?
Aloft Hobbies (Authorized Service Center)
https://alofthobbies.com/radio/frsky-transmitters.html
With respects to switches and sliders differences here is a brief comparison.
Q X7 $100 switches 6
Q X7 SE $184

X9D+ $185 switches 8 + sliders 2
X9D+ SE $257

X9E $315 switches 8 + sliders 4 + add more switches and sliders,

SE -
Upgraded gimbals + Travel case and some other differences such as the sticks.
Other differences as well.
 
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#11
Keep in mind most of the time the limitation is the 8 channel receiver (8 sets of servo pins).
TAER take up 4 channels.
That leaves 4 channels for switches and the potentiometers. Maybe plus 2 channels for gyro/flight controller control.
So 6 switches and 2 potentiometers for most people would be enough.
 
#12
With the 9xd special with the unscrewedable anntana I heard you don't want to keep putting it on and off or the connection will get bad is this true if so could you modify the case that it comes in. to fit the 9xd with the anntana on?
Thanks
Leave it on and don't unscrew it.
If you are a handy DIYer then sure you could make it a fixed antenna.
My suggestion is that when you get it use it for one full flying season before you start with the mods. The FrSKY transmitters are quite good as is without DIY type modifications.
 
#13
Keep in mind most of the time the limitation is the 8 channel receiver (8 sets of servo pins).
...
While it is true that FrSky only sells 8 PWM channel RX, the X-Series RX do support 16 channels, either through S-Bus which can be decoded or by adding a second RX with special binding procedure to bind the second RX to channels 9 to 16. So, with no change to the TX nor JR module, both Q X7 and X9D can transmit 16 channels.
 
#14
With respect to number of channels. Are you into adding gadgets or do you just want to fly without the peripheral distractions/fun?

12 servo channels
An x8R receiver can have an additional 4 channel added using the sbus to pwm coverter.

16 channels
You can also bind two receivers to the same radio on the same aircraft (but make sure teleletry is turned off on the second receiver).

16+ channels

To go above 16 channels you need to add an external module.
Post getting to long and off topic (a bit) so if you want to know more start a new thread and we'll jump in.

How many channels are needed/wanted

4 channels TAER
2 Gyro/flight controller S6R/S8R
1 differential throttle for twin engine
2 Flaps (depending on how the servos and link arms are mounted)
--------
9 channels

1 Gear
1+ for lights
1 smoke
1 candy dropper
1-2 bombs
Keep adding :)
 
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#16
With respect to number of channels. Are you into adding gadgets or do you just want to fly without the peripheral distractions/fun?
Very true. It is rare and questionable if you ever need more than 8 channels. In fact, very few cases would that be wise.

12 servo channels
An x8R receiver can have an additional 4 channel added using the sbus to pwm coverter.
BTW, you can have multiple sbus to pwm coverters Y off the S-Bus output so you can get the full 16 with the X8R and 2 converters.

16-24 servo channels
You can also bind two receivers to the same radio on the same aircraft (but make sure teleletry is turned on on the second receiver).
How are you getting to 24 channels? To my knowledge, the protocol does not support that without adding a JR module (in which case, you can get to 32). If you are thinking (X8R + converter) time 2 that does not get you 24 unique channels as the converters would be outputting duplicates of X8R outputs.

But you do have a good point that when binding the second X8R, be sure to use the binding procedure to have it on 9-16 and telemetry is off: only one RX can provide telemetry.