Comparison of Spektrum Airware Transmitters to the FrSky Taranis Transmitter

Transcription

1 Comparison of Spektrum Airware Transmitters to the FrSky Taranis Transmitter One of the most difficult, yet most important, decisions an RC hobbyist must make is which transmitter to choose. One of the most common decisions users face is choosing between a Spektrum transmitter and the FrSky Taranis. No one can make that decision for a user and the best way to make the decision it to try both systems. My goal with this document is to try and provide facts about the differences between the two systems. A fair comparison is extremely difficult because the programming approaches the two systems take are very, very different. This is, perhaps, the reason opinions often seem so polarized. I like to think I am not biased since I very much like both systems and I refer both systems often. Which I recommend to someone varies based on my knowledge of the person s technical skills, patience, desire for customization, personality, etc. This is not a review; rather it is a comparison with some of my personal comments and opinions included. I welcome comments/suggestions from the community and I have no doubt there will be corrections and additions to this document. Since Spektrum and OpenTX are so different I had to devise a method for comparison. I am certain my method is imperfect and will need tweaking, but it is a start. My method started with a Spektrum transmitter model feature matrix I authored for myself and the Spektrum community. Since every day I see users on RCGroups.com asking for a comparison of the two systems, I thought that using my Spektrum feature matrix as a starting point for a comparison would be a logical starting point and might be helpful. I strongly suspect there will be more Spektrum-exclusive and FrSky-exclusive items added as the community provides feedback. In the interest of full disclosure I must admit that my knowledge of Spektrum-exclusive features is weaker than my knowledge of OpenTX features. I will rely on community feedback to address this shortcoming. I must also note that detailing every possible feature of either system is well beyond the scope of this document. A summary of this entire document could be: Spektrum's quality and powerful radios make programming fast and easy with minimal fuss. But it does get complicated and fussy if you need to go beyond the predefined use cases. Many users will never need to go beyond expected use cases. Going beyond expected use cases means fighting with the transmitter s programming to make it do what you want and, in some cases, is simply not possible. Spektrum s approach is that of a guiding partner. The Taranis is the most flexible system available today. If you want to do it, then the odds are it can be done on the Taranis. But this flexibility comes with a cost of complexity and a learning curve. Some users find the Taranis freedom liberating, and some users find it extremely confusing and frustrating. Taranis approach is that of an open canvas upon which you create. If you like to tinker then the Taranis is a lot of fun. If you are not satisfied with that basic summary then read on if you dare. I have broken the remainder of the document up into sections that are somewhat logical. My reason for breaking it into sections is because I felt like bite-sized chunks are easier to process, especially since I offer comments and opinions on some line items DaddyBigas Page 1 of 15 Document version

2 General hardware DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Transmitter model number SPM6700 SPM7000 SPMR9900 SPM18100 X9D+ Channel count Modulation 2 DSMX/DSM2 DSMX/DSM2 DSMX/DSM2 DSMX/DSM2 ACCST Antenna 3 Single fixed Single fixed 2 fixed (dual diversity) 2 fixed (dual diversity) Single hinged Model memory models 250 models 250 models 250 models 60 models Gimbal 4 ball bearing 4 ball bearing 4 ball bearing 4 ball bearing 4 ball bearing Adjustable stick tension and ratchet Adjustable stick height Modes 1, 2, 3, 4 1, 2, 3, 4 1, 2, 3, 4 1, 2, 3, 4 1, 2, 3, 4 Removable throttle wedges Trainer port Headphones port Telemetry Digital trim SD card slot 5 Wireless trainer link 6 USB port 7 Serial port 8 External module bay 9 System clock (date/time) 10 Rubber comfort grips 11 Primary menu navigation 12 Scroll wheel Scroll wheel Scroll wheel Scroll wheel Buttons USA warranty support 13 Horizon Hobby Horizon Hobby Horizon Hobby Horizon Hobby Aloft Hobbies or FrSky 1 Taranis has 32 channel support in the software. The internal XJT module outputs 16 channels and an additional 16 channel outputs are available via the external module bay. It is possible to split the channels across the internal and external module. This allows one to, for example, use two 8 channel receivers (even of mixed brands) as a 16 channel receiver. Yes, that is really cool. 2 Modulation/framerate support can vary based on regional compliance issues such as EU compliance. 3 Spektrum's dual diversity antenna system on the DX9 and DX18 is clearly superior. I really like this approach. 4 Spektrum wins here based not only on number, but also because Spektrum has moved beyond the outdated concept of each model having a number (or model slots). Both systems can store additional models offline on the SD memory card DaddyBigas Page 2 of 15 Document version

3 5 Spektrum uses a standard SD card, FrSky uses a micro SD card. 6 Spektrum's wireless trainer link is excellent, and their master override feature is very handy. This is a really nice Spektrum exclusive. So nice, in fact, that I built my own wireless trainer for the Taranis. In general I would say Spektrum s buddy boxing capabilities (both wired and wireless) are more flexible. But if using the trainer port for something other than buddy boxing I would say the Taranis has more capability. 7 Taranis USB port is very handy for upgrades and SD card file management/access. 8 Taranis serial port can be used for custom purposes, power tapping, and FrSky receiver firmware upgrades. 9 Taranis module bay is a clear advantage. An external module can be added so any protocol can be supported including Spektrum s DSMX/DSM2! Integration is seamless and it is possible to use both modules (the built-in and the module bay) simultaneously or separately. It is even possible to use, for example, both a FrSky and a Spektrum receiver at the same time. 10 The system clock is used for timestamp information, such as time stamping log files. 11 Spektrum transmitters have a more contoured feel and have rubber grips which make the transmitter more comfortable in the hands. 12 Menu navigation on the Taranis is done via a set of buttons bordering the display. Spektrum s primary navigation method is via a scroll wheel (rotary encoder) which is much easier to use and is a faster method of navigation. Also, the buttons on the Taranis are a known weak point and are known to fail. The fix is simple, but it is an unfortunate design decision that will hopefully be addressed in the future. 13 At this time I will only comment on USA warranty support. Horizon Hobby/Spektrum is USA based and has a reputation for stellar customer service. I have experienced this myself and I can confirm their warranty support is first class. FrSky is a Chinese company and warranty support is not so clear. The best option for warranty support is to use their USA service center which is Aloft Hobbies. Aloft Hobbies has an excellent reputation and I have had generally good experiences with them myself. If FrSky products are purchased from Aloft Hobbies then I know Aloft stands behind them 100% and warranty service is at no charge. I am unclear at this time if FrSky products purchased elsewhere receive no-charge warranty support from Aloft Hobbies. There is really no question here that Spektrum has an advantage when it comes to representation and support in the USA over FrSky. That said, one aspect of the FrSky Taranis that I really appreciate is any and all parts are available for purchase at a very reasonable price which makes self-service possible and also makes hacks or mods easy. Spektrum does not provide parts, nor do they allow self-service DaddyBigas Page 3 of 15 Document version

4 Battery DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Included battery 4 AA 2 Ah 2S Li-Ion 2 Ah 2S Li-Ion 2.6 Ah 2S LiPo 2 Ah NiMh LSD Included battery model number - SPMA9602 SPMB2000LITX SPMB2600LPTX TARANIS 2000MAH Charger power supply included Internal charger Lithium Lithium NiMh Battery chemistry Alkaline, NiMh, LiPo, Alkaline, NiMh, LiPo, supported Li-Ion Li-Ion NiMh, LiPo, Li-Ion NiMh, LiPo, Li-Ion Alkaline, NiMh, LiPo, Li-Ion Switches DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Push button momentary Momentary toggle 1 2 position toggle position toggle Extra assignable digital trim switch Sliders DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Number Position - - back side side Rotary knob DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Number Position - front top top front Switch customization DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Assignable switches all all all all all Digital switch setup 2 Analog switch setup 3 Logical switches 4 Combo switches 5 LCD display DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Resolution 6 192x96 mono 192x96 mono 192x96 mono 192x96 mono 212x64 mono Backlight 2 color options w/adjustable hue 1 Taranis lacks the additional trim-style switches of the DX9 and DX18. However, the 4 primary trim switches are re-assignable for any purpose. 2 Spektrum and Taranis handle this differently. 3 Spektrum and Taranis handle this differently. Spektrum's method is easier to understand, but ultimately less flexible and not available across their entire product line DaddyBigas Page 4 of 15 Document version

5 4 This is a core feature of OpenTx and is huge advantage for the Taranis because the user can define custom conditions to trigger events, mixing, telemetry, alerts, etc. Spektrum s Flight Mode switch could be considered a logical switch, but this is different from the dedicated logical switch offering in OpenTX. 5 Spektrum s DX18 has a dedicated feature called combo switch. OpenTX handles it via the logical switch feature. 6 Spektrum's display is physically smaller but is clearer and of better quality. The Taranis' display is larger so its elements are larger and easier to read for some people, but the Taranis display is clearly of less quality DaddyBigas Page 5 of 15 Document version

6 General software DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Operating system Airware Airware Airware Airware (proprietary) (proprietary) (proprietary) (proprietary) OpenTX (open source) User-upgradeable firmware TX model crosscompatibility All Spektrum Airware radios are cross-compatible within the limits of radio channel count not applicable Programmable rates & expo 1 Model to SD card save/load ModelMatch/receiver lock 2 Cross trim support User timers Function slowing Sequencer X-plus support 5 not applicable Instant trim Customization via user scripting 6 Custom splash screen Custom model images Option to create/edit models on a PC/Mac 7 Simulate transmitter on PC/Mac 7 Copy/paste settings Special functions 8 Global variables 8 1 Spektrum has dedicated GUI for rates/expo. Taranis does it via one of several methods using the inputs and mixes screen. Spektrum's method is easier for many people, but FrSky's method is ultimately more flexible. 2 ModelMatch is a Spektrum trademark. Taranis has something similar called receiver lock. ModelMatch is more much more reliable because it works for all Spektrum receivers and is automatic and undefeatable. Receiver lock only works with FrSky X series receivers and can be optionally defeated. Therefore, FrSky's receiver lock is more flexible but is not as reliable as a safety measure. So Spektrum wins safety-wise, and FrSky wins flexibility-wise. Defeating receiver lock is handy at times so you can, for example, bind one receiver to multiple model memories. But unfortunately OpenTX defaults receiver lock into a potentially unsafe (duplicate) state. So in order to be certain receiver lock is actually using a 2015 DaddyBigas Page 6 of 15 Document version

7 unique ID one needs to manually manage it. I have an Excel spreadsheet where I track my model IDs to make sure they are unique where I want them to be unique for safety reasons. Relying on the user to keep a safety feature in a safe state is not good practice. 3 Taranis timers are more flexible because the user can control start/stop/reset via more options than with Spektrum. 4 Spektrum handles sequencing differently than the Taranis, but both systems support sequencing in their own way. 5 X-plus is a Spektrum feature and trademark. It does not apply to the Taranis because the Taranis supports more channels natively than does any Spektrum transmitter. 6 The Taranis' LUA scripting engine supports an amazing array of custom functionality including custom telemetry screens. This is a nice advantage. 7 Using the free OpenTX companion software one can not only create, edit, and manage models on a PC or Mac, but one can also simulate the entire Taranis transmitter. This is a huge advantage as one can work on models without even having the transmitter in hand and is great for those who find it easier to work on a computer rather than on the small screen of the transmitter. It also makes testing easy. OpenTX can even be used by people that don t own a Taranis to test drive the system. 8 Taranis special functions and logical switches provide the Taranis with levels of customization that cannot be matched by Spektrum transmitters. However, not all users need that level of customization and complexity DaddyBigas Page 7 of 15 Document version

8 Telemetry DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Hardware required to be No module required, it is built into every Spektrum requires the purchase of a TM1000 module for each model with telemetry installed in model FrSky receiver at no additional cost Flight log Flight log format Spektrum log files are proprietary and can only be viewed via a third party viewer Text (CSV) Input (stick) logging Signal strength indication 1 Receiver voltage 2 Current sensor Capacity sensor Variometer sensor GPS sensor Altimeter sensor Airspeed sensor Temperature sensor External voltage sensor Optical RPM sensor Brushless RPM sensor G-force sensor UART bridge Extra analog inputs 4 PowerBox JetCat 1 Spektrum and FrSky approach signal strength/quality reporting differently: Spektrum reports antenna frame loss, fades, and holds. As with all other Spektrum full range telemetry data the purchase of a Spektrum TM1000 unit is required. Also there is a signal strength indicator (bars) on the screen. But the signal strength bars are in indication of the quality of the transmission link from the TM1000 unit to the transmitter so I find them of limited use/accuracy. However, the reporting of frame losses, fades, and holds is very useful both as a safety feature and for troubleshooting. The transmitter can alerts on fades and holds and also records the data in the flight log. Some Spektrum micro receivers/bricks and flight controllers have limited short range telemetry built-in (receiver voltage and fades/holds only). FrSky does not require additional hardware for signal strength reporting via RSSI (Received Signal Strength Indicator). Every FrSky receiver (except for the specialized super long range one) reports RSSI back to the Taranis. The Taranis can alert on low RSSI, record RSSI in the log, and can even trigger custom functionality based on RSSI. 2 Spektrum transmitters report receiver (or BEC) voltage received from a TM1000 unit in the model. The Taranis reports receiver (or BEC) voltage it gets from any FrSky receiver, no additional hardware needed DaddyBigas Page 8 of 15 Document version

9 Flight modes DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Airplane The Taranis has 9 flight modes for any Sailplane model type Helicopter Servo setup DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Reverse Sub trim Travel Trim step options Adjustable step size of 0 10 steps or 0µs 15µs Adjustable step size of 0 10 steps or 0µs 15µs Adjustable step size of 0 10 steps or 0µs 15µs Adjustable step size of 0 10 steps or 0µs 15µs Exponential, extra fine, fine, medium, course Servo balancing Adjustable servo speed Absolute travel adjustment 2 Servo monitor shortcut from main screen Adjustable PPM center 1 I have always found the way Spektrum limits the number of flight modes based on the type of model a little aggravating. I believe the idea is to cater to the most common use cases but I often find my needs outside of standard use cases. 2 Spektrum's DX9/DX18 and the Taranis handle this differently, but both allow minimum and maximum absolute travel specification to prevent overdriving a servo DaddyBigas Page 9 of 15 Document version

10 Alerts DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Voice alerts User customizable voice alerts 1 Assignable sound alerts Ability to decide which alerts are announced at power-up/initialization Vibration alerts (haptic) 2 Adjustable haptic pattern Option to assign volume to switch/slider/knob 3 1 Taranis has a clear advantage here. Since a user can create and use any audio event this puts the Taranis voice alerts in a different league than Spektrum s voice alerts. That said, Spektrum is rumored to be working on a way to customize its voice alerts. 2 The vibration mechanism on Spektrum radios is stronger and feels better. 3 The ability to quickly adjust volume with a knob, switch, or slider is something that almost all Taranis users appreciate and use. On Spektrum radios this important ability is relegated to multiple button presses and is subject to errors and even altering the wrong setting. Master volume control on Spektrum transmitters feels like an afterthought DaddyBigas Page 10 of 15 Document version

11 Mixing DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Number of curve points Up to 7 Up to 7 Up to 7 Up to 7 Up to 17 Preset mixes 3 (4 for sail) 3 (4 for sail) 3 (4 for sail) 3 (4 for sail) none Flap delay + elevator compensation 1 Programmable mixes w/no line limits 3 Normal + curve 5 of 5 8 of 8 8 of 10 8 of of 32 Normal only of 10 8 of 16 - Mix rate increment 1.0% 1.0% 1.0% 0.5% 1.0% Origin mixing Differential DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Airplane (aileron, elevon, & V-tail) Sailplane (aileron, elevon, & V-tail) Differential can be applied to any mix 1 Spektrum handles its flap system (including delay and elevator compensation) via a nice dedicated GUI. The Taranis requires the user to handle it via the mixing tool. Spektrum s approach is an advantage in that is it easier to use for some people, but it can sometimes be a disadvantage in that it can be less flexible. 2 The mixing capabilities of the Taranis are incredibly powerful and flexible. The Taranis mixing tools will do things not possible on Spektrum radios. To be fair, this is largely by necessity since the Taranis does not automatically create mixes for the user based on the model/aircraft type. The power of the Taranis mixing comes with a learning curve with which not all users are comfortable (especially those already used to a different system). 3 Taranis mixes can mix an unlimited number of sources and offer many additional options such as multiplexing control DaddyBigas Page 11 of 15 Document version

12 Airplane wing types 1 DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Single aileron Dual aileron Flaperon Single aileron + single flap Elevon No predefined types but all Elevon B combinations up to 32 channels Dual aileron + single flap supported, user must create required Single aileron + dual flap mixes Dual aileron + dual flap Quad aileron (biplane configuration) Six aileron (large 3D configuration) Airplane tail types 1 DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Normal V-tail A V-tail B Dual elevator Dual rudder Dual rudder + dual elevator Canard 1 servo w/elevon Canard 2 servo w/elevon No predefined types but all combinations up to 32 channels supported, user must create required mixes Sailplane wing types 1 DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Single aileron No predefined types but all Dual aileron combinations up to 32 channels Dual aileron + single flap supported, user must create required Dual aileron + dual flap mixes Quad aileron + dual flap Sailplane tail types 1 DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Normal No predefined types but all V-tail A combinations up to 32 channels supported, user must create required V-tail B mixes Sailplane specific features 1 DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Sailplane camber system No predefined types but all Sailplane camber preset combinations up to 32 channels Motor throttle switch supported, user must create required assign mixes 2015 DaddyBigas Page 12 of 15 Document version

13 Throttle types This section really illustrates how radically different the two brands approach programming. Spektrum lets the user specify the model type, wing type, and tail type and then automatically assigns channels, builds behind-the-scenes mixes, and specifies certain functionality. The more I study how Spektrum is doing this the more I appreciate the amount of work the Spektrum transmitter is handling in the background. The Taranis relies upon the user to specify inputs, channel assignments, functionality, and create the mixes. Spektrum s method is much easier and faster for many people, but obfuscates how things work to a degree and limits some of the customization possibilities. The Taranis forces the user to do all of this work themselves, but in the process there is much more flexibility and customization. Neither approach is better because different users will be more comfortable with one approach versus the other DaddyBigas Page 13 of 15 Document version

14 Helicopter specific features 1 DX6 G2 DX7 G2 DX9 DX18 G2 Taranis X9D + Swashplate normal Swashplate 3-servo 120 Swashplate 3-servo 135 Swashplate 3-servo 140 Swashplate 3-servo 90 Swashplate 4-servo 90 Swashplate 2-servo 180 throttle curve 7-point 7-point 7-point 7-point 17-point pitch curve 7-point 7-point 7-point 7-point 17-point tail curve 7-point 7-point 7-point 7-point 17-point Swashplate timing Cyclic-to-throttle mix Swashplate timing mix Unknown at this time 2 Active gyro & governor trim 1 The Taranis' helicopter-specific offerings here are different and seem more limited as far as automated configuration. It is likely that more work is required of the user when setting up a flybar heli on the Taranis. Similar airplane wing type, for example, it is up to the user to programing the necessary mixes and such. I am not qualified to comment further at this time since I know almost nothing about programming a flybar helicopter. 2 I simply do not know the answer to this one. I will update the document with further information as I learn more from others DaddyBigas Page 14 of 15 Document version

15 Spektrum, DSM2, DSMX, X-Plus, and ModelMatch are registered trademarks of Horizon Hobby DaddyBigas Page 15 of 15 Document version