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Bill Engst and the CAT application—
a program that speeds the manual
tuning process.
a more versatile automated tuning option
dealing with smaller batches for specific
applications. Until early-2004, the speed of
the robot determined the necessary
processing speed of the software. At a safe
speed, the robot could take up to a minute
to execute a tuning stage, moving from one
tuning screw to another, back and forth.
Because of this, the tuning software itself
was not time-critical.
CAT for short runs
Engst’s proposal was to further develop the
tuning software so that it could serve as an
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RF
CONDITIONING
analytical tool for human manual tuning, in
the case of smaller batch runs. “I saw a guy
tuning by hand for a ‘one-off’ customer
and it was taking him so long. That’s when
the light bulb clicked and I realized we
needed to update the software to
real-time,” says Engst.
Based on this realization, RFS developed
computer-aided tuning (CAT) software—a
program that allows a human tuner to
expedite the tuning process. “What
CAT does is collect data, measure a
difference between the data and a
goal, then display this as a bar-graph
on a screen—it updates every half
second or so,” says Engst.
The benefit of the CAT software is that it
allows RFS to tune its smaller volume and
sometimes more-complex filters much
faster, at a lesser investment than the robot,
yet retain the consistent reliability. By
streamlining the tuning stage, each filter
production line has realized increased
throughput as well as a faster and more
flexible response to customers’ orders.
“Initially we’d tested CAT in the lab by
tuning a 10-pole delay filter—which is quite
complicated to tune—and it was able to do
it easily,” says Engst. This proved the CAT
software’s ability to speed the introduction
process of new and complex filters into
commercial production cycles. Also,
because the CAT software actually analyzes
the filter in order to tune it, it knows
instantly if there is a problem with the
unit, which means no time wasted
troubleshooting.
The CAT software was first introduced into
the Connecticut production line in March
2005, and in conjunction with the robotic
tuners, allows RFS to provide its customers
with fast-tracked deliveries of all filters.
“The power of these tools is that they
can look into the filters and know
exactly what’s going on inside,” says
Engst, “Which means there’s no
guesswork—we’re giving our customers
exactly what they’ve asked for, every time
and on time.”
The robotic tuning head takes less than
five minutes for one filter.
The robots running in RFS’s Connecticut
and Hillerød facilities tune up to 150
filters every day.