ETS-Lindgren HI-4457 Isotropic Magnetic Field Probe (Archived) - Manual (Page 26)

HI n 4457 Manual Page — 21
7.0 APPLICATION CONSIDERATIONS
Introduction
The following subsections contain information designed
to help you maximize the effectiveness of the HI n 4457.
Out-of-Band Considerations
Although the HI n 4457 is nominally rated for operation
from 10 MHz to 1 GHz, it may respond to signals both
above and below these frequencies. Such responses
must be taken into account when performing certain
operations, such as zeroing.
Resolution Limitations
Limitations in probe resolution may result in a non-zero
reading when the receiver is zeroed. If this occurs, it
does not necessarily mean either that there is a problem
with the receiver or that your readings are inaccurate.
Receiver linearity is specified as + 0.5 dB full scale: in
addition, the variance of the A/D converter is + 2 least
significant bits. When using the most sensitive range on
a given probe, these specifications create the possibility
that, under zero field conditions, the receiver may display
a non-zero value.
Probe Support Structures
It is very important to keep conductive objects away from
the HI n 4457. Any such objects in the proximity of the
probe may distort the near field and compromise
measurement accuracy. If your application requires
measurements from a fixed position, always mount the
probe on a non-metallic platform, using non-metallic
screws.
Archived 4/2/10