Zephyr 700 Series, Руководство пользователя

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700 Front Panel Operation
Refer to illustration in Section 1
The 700 is flexible, easy to operate, and provides you with the information needed
to tell what's "going on."
The RELATIVE RF meter actually indicates the amount of limiting taking place in the
CARRIER 1 IF/Demod section. The adjustment, directly beneath it, lets the meter be
set to a convenient operating range for your particular signal. The meter is used for a
peaking indicator while positioning the dish or polarizing the feedhorn. Once the
installation is complete, set the meter to an easy-to-remember number. Any future
deterioration of that setting provides a reason to check for system changes or
problems.
NOTE: The meter setting will probably change if a different SCPC carrier
is tuned.
CARRIER 1 & CARRIER 2 meters indicate the audio output levels of each receiver.
CARRIER 1 is always the active channel in single channel (mono) systems. Normal
factory default setting of the meters is Zero dBm into 600 ohms at the balanced output
for a reading of 100 (Zero VU).
Output audio level is adjustable with the controls
below each meter. An internal jumper at the very front of the audio demod circuit board
permits an alternate Zero VU setting to in8 dBm out. Custom zero settings
can be set internally also. --See AUDIO OUTPUTS in Section 4, System Operation
and Customization.
Audio squelch is activated by the presence of a high audio noise level. Whenever
squelch occurs, a red LED illuminates the meter face. Audio muting from the squelch
circuitry can be canceled by depressing the tops of the
SQUELCH DEFEAT switches.
-Although the squelch defeat disables the red meter lamps, the alarm relay action is
not affected.
The DISPLAY is a backlit two-line LCD readout. The bottom line of text is for fault
messages. The top line shows operating frequencies as follows:
TRANSPONDER: Center frequency of the satellite signal in MHz. C band
transponder frequencies must be entered as a number between 3700 and 4200.
Ku band (for the Americas) must be between 11700 and 12200.
CARRIER 1 & 2: Operating frequency of the individual SCPC carrier as down
converted to the "70 MHz Band." Valid frequencies that may be entered are between
50.00 and 90.00 MHz. Four digits
must be entered whether needed or not. -For
example, 81.3 MHz is entered as 8130 and is displayed as 8130.
Front Panel MA700FNT.SAM
SECTION 21