Spektrum HV A6320 & A5070 Servos

Spektrum servos are nothing new, so what’s so special about their new A6320 ($79.99) and A5070 ($109.99)? First, they are high voltage (HV) capable, meaning they can run off a 2S LiPo receiver battery without a voltage regulator. Removing the voltage regulator leverages the advantage of a high-speed servo’s increased speed and torque, while also removing a possible failure point from your onboard radio system. Our flight systems are getting complicated enough, so anytime you can remove the need for a component you increase both simplicity and reliability.

High voltage isn’t the only new feature, however; these servos also have an onboard microprocessor that won’t initialize the servo until it sees a valid position signal from the receiver. When it sees that signal, they soft start (i.e., they slowly bring the servo to its initial, usually centered, position). They do not snap to center like many servos. They even beep to let you know they are initializing properly, and in fact, if you power up the receiver while the transmitter is still booting up, they are quite musical until the receiver connects and they get a valid signal. In addition to soft starting, the microprocessor monitors temperature and current, and shuts down the servos if something is binding up or shorting out.

Each servo’s metal gear train is supported by dual ball bearings. The gears are tightly meshed for low wear and a slope-free control system. Aluminum cases, partial on the A6320 and full on the A5070, assist with dissipating heat, the bane of electronic components. The speed and torque specs on each are impressive.

Another new touch to be appreciated are the servo mounting screws. Phillips screws have been banished, and in their place are easy-to-install and remove 2mm hex-driven mounting screws with a built-in washer, and a 3mm servo arm screw with a lock washer. These are awesome where there is no straight shot to the servo and installations require the use of a ball driver.

The 6320 works well in mid-torque applications where a full-size servo is called for. It will be perfect for many warbirds and smaller gas 3D planes and scale planes. The smaller 5070 is perfect for many RC helicopters and electric models where size is limited but you want a servo that packs plenty of power, precision, and speed.

Specs are great, but how do they work? I installed 5070s on the ailerons and 6320s on the elevator and rudder of my Hangar 9 Extra 330SC that I’ve owned for a couple of years. Wow! The huge surfaces and high speeds were no problem; the Extra was extremely precise with no hint of control surface blowback, even during the most violent maneuvers. If you are looking to replace old servos in your current installation, or doing a new build, give these servos a close look. This sort of performance, with protection from overheating and over current, is going to make them a favorite in a lot of models.—By

I was both pleased and surprised by the noticeably improved feel and response in flight with my new servo upgrade. The Extra 330SC has been one of my favorite models to own, and it will get even more flight time now.

I had to open up the aileron servo pockets very slightly on the Extra 330, but it was worth the effort. The combination of the fast and powerful A5070s plus the end-to-end ball links proved an exhilarating combination.

A nice selection of servo arms is included with each servo. The 2mm servo mounting screws have a builtin washer and work very well.