Transmitters and Receivers - Spektrum Revealed



Let me start with my credentials and why I am confident to say I know Transmitters and Receivers!
  • 1st, I own nearly all the Spektrum & JR Transmitters. Examples include: DX5, DX6i, DX7, DX7s, DX8, JR9503, DX10T, JR11x, JR12x & DX-18.  I also own a couple of Futaba Radios. I have numerous "Comes with the plane Radios" and many many others.

  • 2nd, I have at least one of each of every DSM Receiver by Spektrum.  Examples include: AR6100, AR6110, AR400, AR500, AR7000, AR8000, R-921, R-922, 1220, AR10000, Xplus8, And everything in between including X series and 2 series and the variations of each.  Plus so many other brand and off brand receivers.

  • 3rd, I am an official Test Pilot for Spektrum. Spektrum sends me their new products, like transmitters, receivers, telemetry devices and other cool Spektrum toys to test, report and suggest fixes.

  • 4th, I own planes and helicopters in nearly all the different categories, sizes and types. Such as Micro Profile, UM, Flat Foamies, Parkzone, Eflite, EDF's, Electric, Nitro, Gas, Mid Sized, Giant scale, single engine, multi engine, Warbird, Scale, Jet, 3D, Pattern and the list goes on. See the column to the left!  I currently Own Over 100 aircraft. At one point I had in my possession 148 aircraft. I only sold a few because of space restrictions.  

  • 5th, I FLY ALOT!  At Minimum I fly every Saturday and Sunday from 7am until 1 to 3pm.  I also fly during the week 2 to 3 times for at least 4 hours a session.  I bring to the field 5 to 30 airplanes at a time depending on the amount of time I have available. And its an assortment of planes from EDF's to Warbirds to Foam to Balsa to Fiberglass, Electric to Nitro to Gas Powered.   I belong to 5 clubs in the area and fly with MANY MANY different experience leveled pilots including pilots much better than myself.

  • 6th, I belong to the AMA, I am a club certified Instructor and hold a Turbine Waiver.

     

So, now that I have provided a few credentials to back up the statements I am about to make below, let me also say, there are always exceptions to every rule.  The guidelines and/or opinions I am about to make below are based on part Facts and part my personal experienced Opinion.  I am providing these statements and assistance as a base guideline.  I am sure some people will disagree or have their own opinions and that's ok!  Again, this is based on the credentials I have listed above.

RADIOS VS RADIOS - WHAT SHOULD I START WITH?

 

I hear this question a LOT.  What should I start with? Whats the difference? Some have dual rates and expo? What is that?  Why do I need all that programming in a radio?  Im on a budget but I own a $1500 plane. I just want to fly my small foam planes from Parkzone or HobbyKing, or Nitroplanes and so on.  

Heres the questions I have to ask back.  Whats your budget?  Do you think you'll be getting into bigger planes? How many planes do you own?   Since I can't hear you, let me break this down a bit for you.

DUAL RATES:  Dual Rates is the ability to set your control surface throws to different degrees on 1 or more switches.  Example: Your Elevator. A low rate might mean that the Elevator only goes up and down 20 degrees.  A High Rate might mean that the Elevator goes up and down 45 degrees.  Theres a huge difference between the 2.  Low rates will calm the plane down. It won't pull as hard or as some people say, its not so wild in the air.  High Rates allows the surface to move to it's possible full potential and therefore, the plane can be a handful to handle if you are not experienced.  

EXPO: or Exponential. Expo is the ability to soften the controls around center stick.  With EXPO off: If you move the stick 50%, the control surface moves 50%.  With 50% expo turned on, when you move the stick 50%, the control surface will be somewhere around 40% travel. Once you get to 100% stick movement, the control surface will reach 100% also.  Basically, EXPO softens the movement of the control surface around the center of the stick movement. The further away from the center of the stick, the closer to TRUE 1 to 1 movement you reach on the control surface.  This all depends on how much EXPO you program into the radio.   I go into example EXPO rates for different Dual Rate Settings in my How To SetUp your Plane Basics section.

I have to say this, and for some people, it will anger them.  If you fly a plane without DUAL Rates and EXPO, you truly have not graduated to becoming an experienced and qualified RC Pilot.  Especially a Pilot qualified to offer advise to other pilots.   WOW, thats a bold statement!  I know I know!  I personally know a couple of pilots at my field that would love to argue this point!  But ask this question, have you ever met a Professional Pilot, one who competes or does shows, that doesnt use Dual Rates and Expo??  You won't!  Theres a reason for that!   If you want to fly Willy Nilly and don't care if the plane looks smooth in the air, or don't care if you don't truly have control over what the plane is doing, then continue without Expo or Dual Rates.  "But Robert, I fly without either and I look good up there!"   Thats Fine I say.  I never said you had to follow this rule.   If you want to drive a Car WITHOUT power steering, go ahead.  It can be done, lots of people like it that way.  But why fight the steering when you have the option to have Power Steering to assist you so that you can enjoy the ride!?   Now, I will say this, I met ONE person who flies without either. He flys everything from 200mph planes to 3D giants.  While I notice the small jitters here and there, he does pretty good. He must have built in EXPO in his fingers.  But his 3D and Precision moves are not smooth and constant.  And Im saying he is amazing at flying! He wows the crowd everytime. But we all still notice the inconsistency in his moves.  Thats because he relies on his fingers to compensate for every move.  Why fight this when you can properly set up your plane and radio and have graceful flights that you aren't fighting with every flight.

SO WHICH RADIO SHOULD I GET?  I break down the basics of different radios below for you:

 

DX5:  Beginner, low budget, 1 plane, 5 channels only, not sure if I want to get into this hobby totally.  The DX5 is inexpensive, sometimes included with a plane or simulator.  It can only bind to one plane (Or receiver rather), it does have simple dual rates. High and Low. This is a great radio if you have only 1 plane and want to learn slowly.  You  also have basically no plans to own more than 1 plane at a time.  If you really think you will be into this hobby, then go ahead and move up.

DX6i:  Beginner, low budget, 10 planes, 6 channels, Want to learn with ability to grow a bit.  The DX6i is rather inexpensive, like from $100 to $150 dollars.  This is a great beginner radio. It allows for some basic programming and includes Dual Rates and EXPO.  With 10 planes in onboard memory, you'll be sure to enjoy learning on this model.

DX7s:  Intermediate. Mid Budget, 7 channels, 20 planes Bound, with SD Card backup. With SD Card ability to load and unload limitless number of planes (requires Re-Binding when loading and unloading).  The DX7s has 20 onboard model memory! Much more programming ability with 6 mixes available. This is a true weekend warrior pilots radio! If you want to learn and be able to grow into bigger and better planes, this radio is great for that! The cost is not that much more than the DX6i.  If your budget allows, look into this radio or the DX8.

DX8:  Intermediate to Serious Pilot. 8 channels, 30 Planes Bound, with SD Card Backup. With SD Card ability to load and unload limitless number of planes (requires Re-Binding when loading and unloading).  The DX8 is a truly a remarkable radio. Lots of 3 position switches for extra programming ability. 30 in memory aircraft spots. Back Lit display. 8 channels for even more cool extras in your planes!  Also a great helicopter radio!  If your budget allows, this radio will be with you for a Very Long Time!

DX10t:  Still in Testing Phase. 10 channels with ability to control 18 channels! This Radio is a Tray Style with unbelievable programming and abilities. More to come once released.  

JR 9303 & 9503:  Advanced Pilot. Committed to RC. 9 channels! 9303 has 30 models onboard, and the 9503 has 50 models onboard!  Advanced Programming! Serious Pilots with Serious Planes.  When its time to get serious about larger planes, super scale planes, multi engine planes and those with lots of extras, the 9503 is the way to go.. The 9 means 9 channels, the 50 means 50 in memory aircraft! 50!!!  The 3 means 3 aircraft types. Airplane, Helicopter, Sail Plane.  Lots of programming abilities!  For the serious Pilot with Lots of Planes from small to Giant Scale!

JR11x & 12x:  Advanced Pilot. 11 & 12 channels. High Budget. 30 models on board with SD Card abilities. Advanced Programming! Serious Pilots with Serious Planes.  The 11x and 12x are the Mack Daddy of Radios!  Super Easy Programming, and lots of it!  If you are going 3D in a major way, or Super Giant Scale needing lots of channels, then either of these will do the trick!  I use my 11x for all my 3D planes, big or small. It allows me to dial in even the most sensitive planes and turn them into a smooth professional looking aircraft!   If you are truly a serious RC Pilot, you'll have one of these babies in your hands!

DX-18 :  Pro Class Pilot. 18 channels. High Budget. 50 models on board with SD Card abilities. Pro Advanced Programming! Looking for the Pro Class in Radios at an affordable price? Then look no further. The DX18 is jam packed with amazing abilities! Just to name a few, 16 mixes. 6 Sequences. (Need retracts and Gear Doors to operate in sequence?). Pre-Flight Checklists. Nearly every wing type and tail type pre-programmed and waiting! And so much more!

 

WHAT ABOUT RECEIVERS?  What should I be using?

Let me start this section on imitation receivers, like the orange receivers.  They work. BUT, I would only use these in small foam planes that you will be flying close to you. Under 300 feet.  I know plenty of people using them and using them in larger planes and flying further out, but time and time again, I watch their inexpensive $200 plane crash.  But thats $200 bucks!  Remember, your plane is only as reliable as it's weakest link!  I watch people put $80 motors, $120 ESC's, $50 lipos, $40 servos into a $200 airframe, and then use a $10 receiver!  WHAT???  Are you kidding me?  Thats where you decide to save money?  At the point of CONTROL??   Let me use the CAR comparison again.  You buy a used car. It needs some repair, so you put brand new tires on it. Put in a $800 stereo. Brand new carpeting. Replace spark plugs & wires and put lots of money into tuning this baby up.  The steering wheel is broke. SO, you fasten the Steering wheel back onto the column using a paperclip.  It works great!  BUT FOR HOW LONG???  Seriously??  All that money into making it go and look good and then you go Cheap on the CONTROL?  So when the paperclip breaks, you have no control, the car crashes, possibly hitting other things or people and then after that, you yell and scream and ask "WHY DID THIS HAPPEN TO ME????"   Cheap imitation receivers are for small close up foam toys. 

With that out of the way, lets break down the receivers a little.  With each step up in receivers, you get more and more reliability against signal loss.  There is a difference between brown outs and signal loss.  A brown occurs when the voltage drops below minimum or totally to the receiver. This is usually caused by low receiver battery power or an issue in the BEC. This can happen on ANY receiver!  Use a cheap old battery, and your chances increase for a brown out. Over power your ESC with built in BEC and same thing, brown out!  Or even Black out!  Either way, you are looking at a plane going down if it doesnt recover fast enough.  Signal loss occurs when the antenna can no longer pick up the signal from your radio!  This will happen to any maker of receivers.  So what do you do to overcome this issue?  There are several things to prevent this from happening.  The main factor is Interference!  This can come from cell phones, Wi-Fi devices, cell towers, other transmitters etc.   For starters, I do not fly with my cell phone on me. I fly at fields with no cell towers near by.  The 2nd step I take is to determine the right receiver for my plane.  If you are flying a small foam profile plane and keeping it fairly close, like under 500 feet, you can get away with receivers like the AR6100 or AR500.  Receivers with no Satellite antenna.  The interference to them is minimum.  You are also looking at weight and space saving concerns so these small receivers work well with them.

Once you get into Balsa Planes, EDF jets, Nitro Engines, Gas Engines or any plane you plan on flying more than 500 feet away, get a receiver with Satellite Antenna.  The minimum I would use is the 6200 series.  These are 6 channel with 1 satellite antenna.  It offers redundant reception so that if one antenna is having bad signal, the other picks it up.   Remember, interference can also occur from the motor, ESC, vibrations from the Nitro or Gas Engine, flying to far, low Transmitter battery strength, and even from the airframe itself.   

  On all my EDF jets, I even place the satellite antenna on the outside of the plane. 

I personally recommend using at least an AR7000 series or higher receiver.  These offer data logging, telemetry abilities and one or more satellite antennas.  In my more expensive planes, I use at least the R921 or R922 receivers. These offer 2 or more satellite antennas and I have NEVER yet, had a signal Loss from these.  

Now, no matter how good a receiver you get, if you put the antennas in bad places, or have the transmitter antenna pointing incorrectly, you increase potential signal loss.  You want to try and keep the receiver and satellites away from power sources and lines as much as possible.  You want the receiver antenna and the satellite antenna perpendicular to each other.  If one is set is pointing horizontally, then put the other vertically.  Your goal is to get the antennas pointing in different directions to pick up signals from the transmitter in all possible positions you can get.

 

With the Transmitter antenna, remember this, the weakest point of signal is from the very tip of the antenna.  Pointing your antenna right at the plane is the worst possible position for it to be in.  I keep my antenna to the right at a 45 degree angle. This maintains that in nearly all positions the side of the antenna is pointing towards the plane, the side with the strongest signal.

If you must crash a plane, make sure it was because you were trying something cool, not because you had signal loss from using the wrong receiver and bad placement of the antennas.

FINAL THOUGHTS:  Remember, these thoughts are my opinion, based partly on Facts and Personal Experience.  There are many exceptions to the rules.  I would never tell you that you can't do something. There are plenty of people that would say otherwise.  There are plenty of different planes and setups and so many levels of pilot skills.  Each warrants it's own special look at how a plane is controlled, powered and setup.  This is intended as a basic starting point and in no way am I implying that every thing above must followed to the letter. 

GOOD LUCK, HAPPY FLYING and may the sky and gravity be kind to you!  ~~Robert Griffin (AKA: RCREDBARON)