Radiolink AT9S Pro 10/12 Channel RC Transmitter with R9DS Receiver - Long Range Radio Controller for Drones, RC Airplanes, Cars, Boats & FPV Racing | Perfect for Aerial Photography, Racing Competitions & Outdoor RC Hobbies (Mode 2 Left Hand)

The AT9SPro might be the best TX unit I have ever used. I would argue against ANYONE that it is the most versatile controller and the best value too! There may be radios that are better for a specific type of pilot (FPV quad fans who are for some reason addicted to Open TX seem to love their Taranis and Jumpers and clones. I will detail below why this radio is utterly superior!)RANGE: Firstly, the range on the AT9SPro is the best out of the box I have ever experienced. It is ROCK solid. For half the price of a Spektrum DSxx, you get all that awesomeness and more... like CRSF more. It combines DSSS and FHSS with error correction for a superior 2.4ghz signal that, as the other reviews have also stated, is as advertised. In an open area with relatively little interference, you can fly for miles. It is incredibly low latency at 3ms (just destroys the competition in this regard) and radio discrete as a unit can be (it will in no way interfere with any other device.) There is a 99% chance that this controller is more than you will ever need. Buuuut, if for some reason all of this will not satisfy you THIS THING IS CROSSFIRE (CRSF) COMPATIBLE. Say whuttttttttttt? You can hook up a TBS Crossfire unit and fly beyond comprehension in terms of range and latency. There is nothing in this price range that comes close to this level of range, low latency, and signal durability. Period.TELEMETRY: The AT9SPro supports native telemetry. With a PRM-01 or PRM-03 (telemetry modules) you can inject a telemetry stream into your 2.4ghz signal. You do not need a separate frequency or transmitter. Less to power and less interference! Plug in the appropriate PRM into your FC telemetry port and the other end into the Radiolink rx (the rx has a port on the top of it) and voila you get realtime telemetry on your controller display. With the PRM-03 you get all the info you could want. In the harrowing moments, the reassurance of real-time information at incredible distances has helped me keep my cookies in the jar. MAKE SURE YOU BUY THE TELEMETRY UNIT FROM A GOOD VENDOR THAT INCLUDES THE CONNECTOR CABLES. This was a major nightmare in the past, but a tiny bit of research or messaging the seller could save you a huge headache.NOT OPEN TX: I get it. The FPV world loves OPEN TX. I personally hate it. Lots of work for nearly no pay off. COMPARED TO THE AT9SPro: You will not get better P-mix. You will not get better telemetry. You will not get lower latency. You won't be as power efficient. (Pros can't run out of batteries at the end of a job / day / week.) Plainly stated: This unit just works! I am not the only reviewer of Radiolink products who has noted that they are far easer to configure and operate than a similar FrSky or Futaba controller. Furthermore, while Open TX is cool in that there are a TON of people supporting it online, like any community based project Open TX can and does have bad iterations. The AT9SPro is not for people who want to customize controller firmware with the bleeding edge. It is for professional operators and pilots who demand performance reliability and ease of operation during flight. If the worst that will happen if you crash your drone is damage to your drone, Open TX is for you. If you will be flying a commercial operation over client property with hazards in flight and below, this is the type of controller you need; One with professionally developed firmwares that are in fact closed source, precompiled AND JUST WORK! Radiolink does a great job with firmware updates, including GREAT tutorial videos regarding their products.PROTOCOLS: All TX/RX units can support PWM and PPM these days. Few as well as this unit does though. Remember that great signal? Well, it isn't just strong, it is quiet. You will get zero servo jitter or drift due to RF interference with an AT9SPro. If you fly planes and gliders especially, this may be of great importance to you as many planes are wired to fly PWM with 1 wire per servo. This unit is awesome for it! Of course that's not all. The AT9SPro features SBUS connectivity as well for a more robust and faster digital serial connection. And it can run PWM and SBUS simultaneously just in case anyone needs that kind of redundancy. Again, not super pertinent to FPV flyers, but of note for commercial operators.GIMBALS: Before anyone begins their lecture about hall gimbal superiority, they are not superior. They have advantages and disadvantages compared to pot gimbals. Good pots beat bad halls every time. Good pots are UTTERLY SUPERIOR to halls when you need low RF noise. Oh yes indeedy, those hall gimbals all the FPV guys love are WAY hotter in terms of interference. I'll take two high quality pots next to my transmitter ALL DAY. I am not flying through foam hoops in my local community center with a whoop. I'm flying a hexacopter over many miles a day. It is my understanding that Texas Instruments has developed the first driftless hall sensor as of this year. It is also my understanding that there are precisely zero controllers with this kind of hall sensor as of 2020. Maybe by the 2.0 of the new hall sensors they will have addressed the RF issues. For the time being, I'll stick with a high quality pot gimbal. The ones on the AT9SPro are slick.BUILD QUALITY: Is top notch. Every seam is tight. Every part is installed to micrometer tolerances. There are multitudes of switches, dials and sliders all of which are easily assignable and customizable in the menus on the controller without needing to connect to a computer. It should be noted that outside of firmware updates, you really do not need a PC to program the controller. The unit really integrates nice hardware with great firmware to make a self contained tool. Even the screws that hold the case together are thick real screws; the kind you see holding a tool together, not the tiny little ones you see holding a typical RC unit together. (One of those weird engineering things that speaks to the philosophy of a company. It is my humble belief that the folks at RadioLink took the time to consider the needs of professional operators and high end hobbyists and have offered the ATxx series of controllers to fill that market.For the record: Paid full price. I just love this unit, and I think that MANY pilots would be better served by using a unit like this. For the professional pilot, especially those who are new to the industry and need to minimize variables while still maximizing performance on a budget, this is an amazing option.I could go on... Suffice it to say this is a LOT of professional controller for the money. Whew! Please be safe and have fun flying!