ETS-Lindgren HI-3603 VLF Survey Meter - Manual (Page 7)

HI-3603 VDT/VLF Survey Meter
© ETS-Lindgren, August, 2005
Revision E, Part #H-600042 7
1.0 INTRODUCTION
The HI-3603 VDT/VLF Radiation Measurement System is
designed specifically to measure electromagnetic emissions
produced by video display terminals (VDT's), computer monitors,
television receivers and other devices using cathode-ray tubes
(CRT's) for information or data display. While a number of
scientific research studies have been completed, there is
currently no definitive evidence of a hazard to VDT users that
may come about from the electromagnetic field emissions at
typically encountered levels. Despite the absence of a confirmed
hazard impact with VDT use, there is an increasing interest in
performing baseline surveys of employee exposure to VDT
emissions in the automated office environment. The HI-3603
VDT/VLF Radiation Survey Meter has been designed to permit
rapid and accurate measurement of the electric and magnetic
fields generated by VDT's and is rapidly developing a reputation
as the instrument of choice for such surveys.
The HI-3603 VDT/VLF Radiation Survey Meter is but one of a
family of measuring devices that covers a wide range of
electromagnetic field measurement needs. The HI-3603 has two
switch selectable sensors for measuring both electric and
magnetic fields. The instrument’s capabilities include data
logging, waveform output, full auto-ranging, and a custom Liquid
Crystal Display (LCD) with a bar graph, as standard features. All
selection and control functions are input from a front panel
membrane switch. True RMS detection assures accurate
measurements of complex waveforms. The waveform output
jack allows observation and evaluation of the actual waveform
being measured. The data logger feature captures up to 112 field
readings for later review using front panel controls.
Microprocessor technology is incorporated in the HI-3603 to
provide for automatic range changing (manual range changing
may be selected) and automatic zeroing of the instrument.
The unique nature of the VDT as an RF radiation source
demands that rather innovative approaches be taken to
accurately assess the magnitude of the emissions (see the
section marked VDT Characteristics for more explanation of the
characteristics of VDT's). Building on the pioneering