Marconi Instruments P4428, Техническое руководство

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Operating and Technical Descriptions
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P4428 GENERAL DESCRIPTION
The P4428 hand -held thermal imaging camera uses the P8092 pyroelectric
vidicon, and provides a thermal television picture in the 8 to 14 micron
radiation band. It is enclosed in a sealed injection moulded polycarbonate
case and is intended for use in fire-fighting applications. The camera is a self
contained unit with a wide-angle germanium lens, giving a viewing angle of 57
degrees, with an integral viewfinder/monitor. The camera is fully automatic
with operation selection of 'Panned' or 'Chopped' mode of operation. Power is
provided by a reloadable battery cartridge which fits into the voltage stabiliser
unit attached to the camera harness. A video output socket is provided for
remote surveillance.
Where difference exist between the versions of camera those for the surface
mount board set (SMT) are given in square brackets [................].
1. ELECTRICAL SPECIFICATION
1.1. Power Requirements
The equipment requires a 9.3 to 15 volt supply at approximately 0.4
amps. A battery cartridge is provided which uses 10 standard 'AA' size
1.5 volt disposable alkaline cells.
∗
The output from this pack is 15 volts
nominal and is regulated to 8.7V and current limited to 700mA by the
voltage stabiliser unit. At least 1.5 hours operation is possible on each
set of batteries. For use with external power supplies an adaptor is
available.
Alternatively 10 rechargeable AA cells (type NCC-50) may be used
with a reduced operating time of approximately 1 hour, depending on
cell capacity.
∗
See also Appendix 1.
1.2. Video Output
Composite video is supplied to an internal viewfinder/monitor. A BNC
video output socket is provided for an external monitor. This requires a
75
Ω
termination. Circular blanking is added to obscure edge effects of
the over-scanned target.
1.3. Performance
In the panned mode the temperature resolution at the centre of the field
of view is less than 0.5
E
C differential scene temperature at a spatial
resolution of 100 TV lines and better than 0.2
E
C at 20 TV lines,
assuming unity emissivity. (See also P8092 data sheet).