5 FLIGHT TESTS NORTHEAST SAILPLANE PRODUCTS ...

The Hitec Digital Servo Programmer can also be used to test any brand of
transmitter for the pulse sent to the receiver as well as the servo voltage
and proper servo-arm movement.
A digital servo's rapid updating also creates a stronger
control-arm command. For example, if you try to rotate the
servo arm of a digital servo from the position it has been commanded
to hold, it will attempt to correct that position six
times faster and thereby develop its maximum torque much
more quickly than a standard servo. A standard servo does
not develop its maximum torque until the servo arm has been
displaced many degrees from its desired position. In contrast,
the digital servo reaches its maximum torque after a much
smaller rotation of the servo arm. This gives the digital servo
a much greater centering position and much more power.
That is why you'll often notice a high-pitched hum emanating
from a plane that uses digital servos. The sound is generated as
the digital servos labor to continue holding the output
shaft's position.
CUSTOMIZE YOUR DIGITAL SERVOS
With their precision and powerful performance, digital servos
have a lot to offer, and some brands even allow you to reprogram
their microprocessors. All Hitec digital servos are programmable
with the HFP-10 Digital Servo Programmer that
allows modelers to change the travel direction, servo speed,
neutral point, endpoints and fail-safe position.
Of course, you could program all of that through higher-end
computer radio systems, but if you program the servos, you'll
be able to use less equipment inside the aircraft, and that saves
weight. For example, dual flaps or dual-elevator surfaces require
one servo to operate clockwise and another to operate counterclockwise.
This typically requires two extra channels on the
receiver for each servo plug, and then the appropriate channels
have to be mixed together. With the HFP-10, each digital servo
can be programmed with the correct rotation, identical deadband
width, neutral points and endpoints. Now the two servos
can be plugged into a Y-harness and then into one channel on
the receiver without any radio mixing.
The latest generation of Hitec servos comes with a custom-designed,
programmable circuit and the super-durable Alumite/MP gear train. The
powerful HS-5645MG is perfect for high-torque applications, while the
HS-5245MG Is Ideal when a small, lightweight, high-speed, high-torque
servo is needed.
MAY 2005 73