ACOSUN HJ Digital Servo Tester / ESC Consistency Tester for RC Helicopter Airplane Car

This item is very well built, Looks good, and functions very well. I was very pleased with the way it worked in both testing servos and centering them. It came quickly and was packaged well. I would recommend this tester.

Happy that so simple design worked this well. Generates good data.

This is a nice servo tester and does what it says it does. The knob is a bit small, but it works well to set a pulse width. It has a feature only kind of indicated on the Amazon page - when the tester is in Auto mode, S - 3, the knob adjusts the speed the servo moves back and forth.I found two issues. The first is that the pulse width range is not wide enough to drive servos to their extremes. In fact it's more than 10% short, both on the low and high side. The Pulse width varies only from 0.8 to 2.2 which is not wide enough. This only commands servos through about 160 degrees or so, not the 180 that many can sustain. It should be 0.5 to 2.5 or so.The second, very minor issue, is that the 'S + -' (Signal, +V, Gnd) are stenciled on the top and it's not clear whether the S pin is at top or bottom. It's at the top, Gnd is at the bottom. But I had to guess.

Simple and affective servo tester. It works for analog and digital servos. I mainly use it to move my retracts for setup and transport at the field. I taped a 5 cell NiMH battery to it and I have a complete solution. It feels sturdy but less expansive then the “name brand” servo “programmer”.

I’m using it to control a servo on my boat for a remote throttle. I’ve had it out twice now and it works great and gives a lot of throttle adjustment.

First It will not work with a wire extension. I wanted to use it to test the extension leads I made, no luck. Then I read they give a warning about setting it correctly and plugging in "the steering servo to avoid damage to the steering servo." I don't know what they mean by a steering servo and I don't want something that can damage my servo. This is of no use to me and is going in the trash

Works great! Simple to use. Quick and easy. Setting up controls in a new plane is much easier as preliminary set up can be done before receiver is installed.

Good tool, cheap finish, does his work