SteppIR 4 Element Yagi, Instruction Manual

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SteppIR Antennas - 4 Element 8
SteppIR Design
Currently, most multi-band antennas use traps, log cells or interlaced elements as a means to cover sev-
eral frequency bands. All of these methods have one thing in common–they significantly compromise
performance. The SteppIR™ antenna system is our answer to the problem. Resonant antennas must
be made a specific length to operate optimally on a given frequency.
So, instead of trying to “trick” the antenna into thinking it is a different length, or simply adding more
elements that may destructively interact, why not just change the antenna length? Optimal perform-
ance is then possible on all frequencies with a lightweight, compact antenna. Also, since the SteppIR
can control the element lengths, a long boom is not needed to achieve near optimum gain and front to
back ratios on 20 - 10 meters.
Each antenna element consists of two spools of flat copper-beryllium tape conductor (.54” Wide
x .008” Thick) mounted in the element housing unit. The copper-beryllium tape is perforated to allow
a stepper motor to drive them simultaneously with sprockets. Stepper motors are well known for their
ability to index very accurately, thus giving very precise control of each element length. In addition,
the motors are brushless and provide extremely long service life.
The copper-beryllium tape is driven out into a hollow fiberglass elements support tube (see below),
forming an element of any desired length up to the limit of each specific antenna model (a vertical uses
only one side). The fiberglass elements support tubes (poles) are telescoping, lightweight and very du-
rable. When fully collapsed, each one measures approximately 48” in length. Depending on the
model, there may be additional extensions added to increase the overall element length.
The ability to completely retract the copper-beryllium antenna elements, coupled with the collapsible
fiberglass poles makes the entire system easy to disassemble and transport.
The antenna is connected to a microprocessor-based controller (via 22 gauge conductor cable)
that offers numerous functions including dedicated buttons for each ham band, continuous
frequency selection from 40m to 6m (depending on the model). There are also 17 ham and 6
non-ham band memories and you can select a 180° direction reversal* or bi-directional*
mode and it will adjust in just about 3 seconds (* yagi only).
Boom
Element Housing Unit
Element Support Tube
Stepper Drive Motor
Copper Beryllium Tape
Copper-Beryllium Tape