An improved technique using a metal or ferrite tuning screw
for an SRR-loaded waveguide was proposed in .
First, we measure the filter when the tuning screw
in the two different position states, then the coarse model parameters is extracted by the Cauchy method.
A very small shift of central frequency is attributed to the absence of a frequency tuning screw
In this step, the coefficients of the network model are produced, then the parameter is extracted by the vector fitting technique , and the tuning screw
positions are predicted by the ASM technique.
Then do the same with the other tuning screw
. From there, simply advance the screws against the barrel uniformly.
They also require a tuning screw
for accurate setting of frequency and special mounting operations, which results in high material and labor costs.
As it has been mentioned before, there is direct correspondence between coupling matrix entries and tuning screw
elements, and therefore also between its deviations [DELTA][m.sub.r] and [DELTA][z.sub.r].
A tuning screw
of about 1/3 the junction width diameter, having a radial bottom and placed in the exact center of the side wall hybrid junction, is an efficient tool for fine balance and return loss adjustments.
Capacitor tuning is accomplished with a unique nonrotating torque mechanism that keeps the tuning screw
head position fixed in the axial plane, permitting the use of an O-ring to accomplish a 40 psi dynamic environmental seal without requiring separate seal caps that can fall off and cause short circuits.
In general, adjustments made to the doubly-terminated filters consisted of modifying the input connector probe length and the first tuning screw
, converging to the single terminated design.
a = wide dimension of the waveguide b = height of the waveguide Select a standard size tuning screw
. The radius of the screw should be approximately one-tenth of the wide dimension of the waveguide.
Design considerations include: Probe dimensions (length and width), coaxial transmission line dimensions, distance from the probe to the backshort, and tuning screw
placement and diameter.