Globact RC Digital Servo r/ESC Consistency r for RC Helicopter Airplane Car(Servo r,ESC Consistency r,RC Helicopter r Tool)

Works great for rc hobbies.

This is a convenient little unit, but it's limited to only 800-2200 μs pulse width, so it only uses about 120°of SG90 servos (which have a range of 500-2500 μs). The "sweep" setting is supposed to be variable speed but its speed is constant, regardless of the dial setting. It doesn't come with any useful instructions (the packaging has very limited info) so I had to look up how to use it on YouTube, and the labeling on the device is unclear. The "S+I" label is actually "Signal, Positive, Negative" and refers to order of the first column of 3 pins (Signal at top). The remaining 4 columns of pins are for servo motors, with the same pin order (Signal, Positive, Negative) as the input pins. Using an external PWM signal overrides all functions of the device (external PWM cannot be toggled from the device), effectively turning 1 servo connection into a 1-channel, 4-port connection. The device will sometimes (erratically) switch between signaling frequencies (50/125/250 Hz) when switching between modes, causing motors to buzz & jitter until the frequency setting is switched back to 50Hz. FYI: the device does NOT show the pulse width of an external signal.

Handy little gadget to use to preset servo to neutral before installation. It also checks moves the servo through a significant portion of the range, which is also useful during installation. If needed, you can set the servo to a specific position anywhere within its range. It also allows up to four servos to be synchronized to the same position.

So took me some effort to figure out how to wire this thing as the packaging has no explanation and on-product labels are WAY OFF and confusing. Had to go and look up the pictures on Amazon to figure that out. So if you for some reason lose the access to Amazon, good luck figuring it out. (so make notes). Otherwise it seem to work fine. One of the functions that is not listed on packaging or in the Amazon description is the "S" signal. As I understand, this is typically designates the "Serial Port" on the Buss-Type Servos. Not sure if this one supports it or not.

Didn't know what to expect when I ordered this device. It turns out to be very useful. I especially like the ability the 'center' up to four servos simultaneously. It doesn't take up much space in my small work area. Great value!