I am now 80 years old and in poor health, so I have decided that my designs should be documented to allow others to build my U/ Tronics Control (U/T) units. I will start with the
single-channel unit, with the multichannel (four to
seven channels) encoder and decoder units to follow. I
coined the name U/Tronics Control in 1982. U/Tronics
Control stands for U/Control (Control Line or CL) with
electronics added. All UT units are designed for use
with standard, not digital, servos.
To verify the accuracy of these instructions, I asked
Mike Boucher if he would build a set of units if I
supplied all of the material. Mike agreed, and after
each unit was built, he shipped it to me for testing. All
three units that Mike built worked right out of the box.
I want to thank Mike for taking on this project. There
are three other people who deserve a big thank-you:
Mike’s wife, Robin, and his daughter, Rachael, for
allowing Mike to do this, and my wife, Pat, who has put
up with my hobbies for 55 years. Thank you, ladies!
The typical use of a U/T single-channel unit is for
throttle control for your CL model without needing to
switch to a three-line control system. It even works
if the insulated lines are slack! It can be used in CL
Scale, CL Navy Carrier, and CL sport flying.
When teaching a new or rusty pilot, if he or she
gets dizzy, you can slow the airplane or cut the engine
completely and land. It is fun to do multiple touch-and-gos in a single flight.
The U/T single-channel unit is controlled by varying
the resistance between the brown and green wires
with zero ohms giving an output pulse width of 0.9
milliseconds every 20 milliseconds and 10K ohms,
giving an output pulse width of 2. 1 milliseconds every
20 milliseconds. This will control almost any analog
servo or ESC.
Study the pictures while reading the instructions. I have
60 years of experience in electronics, so I will try to not
leave any “obvious” steps out.
37 Model Aviation JUNE 2015 www.ModelAviation.com
HOW TO BUILD
by Clancy Arnold