TM 11-6625-3081-23
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DAYSIDE TEST BENCH 2A1 (cont)
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f.
LASER POWER METER 2A1A7 AND RADIOMETER HEAD 2A1A8
(1) General.
The laser power meter and the radiometer head form a portable
system used measure the output of the laser tracker unit and laser transceiver
UUTS.
When in use, the meter is placed on top of the laser protective cover and
plugged into receptacle J3 on the test adapter panel assembly 2A2A4, for AC power. A
cable connects the laser power meter to the radiometer head, which is positioned in
the laser path.
The radiometer head functions the same as the internal radiometer
assembly (2A1A2A3), but over a different spectral range.
(2) Functional Description.
A silicon photovoltaic detector in the radiometer
head transmits signals to amplifier Al in the laser power meter. Output of amplifier
Al is calibrated using front panel AMBIENT ZERO control. A range selector switch
provides system sensitivity over six full-scale decades. Amplifier Al output is
transmitted to amplifier A2 through wavelength selector switch. The wavelength selec-
tor switch is a six-position switch on the rear of the radiometer head. It is used to
select one of five standard laser wavelength positions that have been calibrated
(internal adjustments) for direct readout of power or energy. The remaining switch
position permits the photocurrent to be measured directly. An automatic wavelength
annunciator on the front panel of the laser power meter provides a visual indication
of the measurement wavelength selected.
Amplifier A2 output is displayed on a digital
meter located on the front panel of the laser power meter.
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