ORBIT FR Field Probes - Manual

Field Probes
Field Probes Overview Lightweight: AL-4607 Series
High Accuracy: AL-4608 Series
Aperture Field Probe systems are used to evaluate the extraneous signals
which exist in the location of the Device Under Test due to reflections, other
transmitting sources, etc.
The Aperture Field Probe can rest on a polarization positioner which moves on
a linear carriage, which is mounted on another polarization positioner. Thus a
circular area can be observed at any location in any desired polarization.
The carriage rotation is achieved by a standard polarization positioner, AL-560-
1P, AL-760-1P, AL-1260-1P or AL-1760-1P according to series and carriage
size.
The linear slide is used for the radial motion.
The main purpose of the probe polarization positioner is to keep the probe in a
constant polarization by rotating in reverse direction to the Field Probe
polarization positioner. For example, if the probe is in vertical polarization at a
given position, and the Field Probe rotates 30°, then the probe itself rotates -30°
to retain the same vertical polarization. The probe polarization positioner can
also serve to sample the field at several polarizations at any given point.
It is recommended that the probe be mounted on the smallest polarization
positioner which complies with the probe's mechanical constraints (weight and
bending moment).
Options for both series include:
Rotary joint for the probe positioner
 RF cable installation
 Probe fixtures
 Replace the synchro transducer with Incremental rotary encoder. This option
is required when using AL-060-1P or AL-160-1P positioners
 Preparation and installation of absorbing material
AL-4608-1