VITAL STATS
MANUFACTURER: Hitec
PRODUCT: HS-7950TH Torque Servo, HS-7940TH Speed Servo
FITS: Electric and Nitro Vehicles
PRICE: $149.99 (each)
THE GOODS
Hitec has recently released two new high-end digital servos, the HS-7940TH (High Voltage Speed) and the HS-7950TH (High Voltage Torque). Both of these super-servos are engineered with state-of-the-art features, including durable titanium alloy metal gears, a dual ball-bearing supported output shaft, heat sink case and the ability to run on a 2-cell LiPo battery pack. One of the coolest features, however, is that both of these servos are programmable! Using one of Hitec’s Digital Servo Programmers (HFP-20, HPP-20 or HPP-21), you can tweak any of the servo’s functions, including dead band width, direction of rotation, speed of rotation, end points, neutral points, fail safe (on or off), fail safe point, resolution and overload protection. This allows you to fine tune your servo’s action no matter what application you choose to install them in. Included in the cool (and reusable) see-through container is a small bag containing a few servo accessories (for ground or flight applications), some additional screws and a blue aluminum servo arm. I removed the stock plastic arm and installed the blue aluminum one on both servos to give the titanium gear train a real workout.
TESTING
My trusty Team Associated RC8T seemed the likely candidate to test the two new servos. It’s fast, heavy and I really need some good servos to precisely navigate it around the track. Installation is pretty straightforward; slide the servos into place, lock them down with the included screws, hook up the linkages and plug the servo leads into the receiver. At the track, I used my Futaba 4PK to adjust the steering and throttle servo end points. I could tell right away that the HS-7950’s 486oz of torque and .13 seconds operating speed was going to be no match for my RC8T! I started my first lap off a little slow to get accustomed to the new Hitec servos and soon realized I was dead-on in my assumption about the steering servo; any quick flick of the steering wheel resulted in the RC8T changing directions without a fuss. Even at a standstill the HS-7950 would rock the truck back and forth! What I hadn’t thought about, however, was how the HS-7940TH throttle servo was going to perform. The response is silky smooth throughout the entire power band. Its .06 second operating speed and 222oz of torque was plenty to go from full throttle to full brake by the end of the straight. The titanium gear train held up to a full 5 tanks of fuel on the rough track and even had its share of abuse on a couple, umm, mishaps. There were a couple of times where I would clip a pipe or get the jump or landing wrong. Both servo’s held up to some tumbles and cartwheels but continued to respond as if they were brand new. Front start to finish, the HS-7940 and HS-7950 kept the same speed and precision you’d expect from high end servos like these.
WHAT THEY GOT RIGHT
• Titanium gear train
• Heat sink case
• “G2” second generation programmable digital circuitry
• High performance coreless motor for precise centering and accuracy
• Dual bearing supported output shaft
WHAT COULD BE IMPROVED
• A racing high-speed/high-torque WATERPROOF version would be cool!
CONCLUSION
Hitec claims that these 2 servos will work with any 20-120 Class Aircraft, 30-90 Class GP or 600-700 EP Helis, 1/10-1/4 Scale Cars (for throttle and steering) or any GP or Gasoline Boats. After 40 or so minutes of bashing around the track, it’s pretty safe to say there’s not a vehicle that these servos WON’T work in! Both are extremely smooth and blazing fast! In addition, if you do end up getting one of Hitec’s Servo Programmers, the options for these are endless. So, when it’s time to upgrade your servos, do yourself a favor and lay down the buck-fifty (per servo). They will definitely be a pair of the last servos you’ll ever buy.
LINKS
Hitec: www.HitecRCD.com (858) 748-6948
Team Associated: www.TeamAssociated.com (949) 544-7500
