Motorola R-2001A, Руководство по обслуживанию

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The frequency indicated at the top of the screen is now that of the desired incoming signal. It can also
be monitored for call signs, etc.
NOTE
The spectrum analyzer is functional but uncalibrated for level measurements in
Power Monitor mode for transmitter testing with the built-in 125 watt 50 ohm load.
(Observe "RF LOAD OVERTEMP" warning for high power levels or extended
periods of use.)
Figure 4-6. Spectrum Test Setup and CRT Display
4-12. MONITOR. The analyzer is capable of monitoring the same frequencies that it generates (para 4-9).
Select Gen/Mon Mtr in the DISPLAY column and the modulation type in the FUNCTION column. Set the
FUNCTION switch to the Monitor position for small signal samples or off the air monitoring. For high power
signal monitoring (0.2w to 125w), set the FUNCTION switch to Pwr Mon.
CAUTION
To prevent undue stress on the protected circuits it is advisable to always switch the
system to the power monitor mode before applying power in excess of 200 mw.
Additional protection is also obtained by making it a practice not to leave the step
attenuator in the 0 dB position.
NOTE
High-powered equipment in the 1-30 MHz range, which has unusually fast carrier
rise times, may damage the system analyzer with repeated activation of the protect
circuit. Ensure the FUNCTION switch is in the Pwr Mon position (this enables the
protect circuit) before RF power is applied to the equipment.
In the monitor mode the CRT displays the type of signal being monitored, the selected frequency, power, error
of the received frequency, and the modulation level.
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