Rohde & Schwarz VOR/ILS Analyzer EVS200, Руководство пользователя

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VOR/ILS Analyzer EVS200
0796.1800.02 E-8 40
Chapter 3: Operation
Command FA2
command function
FA2 <Fast DDM measuring on> Activating the Fast DDM measurement
The command FA2 switches on the fast DDM measurement. The measuring, used only for landing
path measurement can only be activated through a controller.
The command FA2 performs the continuous measurement and output of the DDM, RF level, Mod-
factor 90 Hz and Modfactor 150 Hz with a transmission speed of about 20 measurement value sets
(DDM, RF level, AM90, AM150) per second. This conforms to a time interval of 50 ms. The stated
RS-232-transmission times are related to 19.200 Baud.
The measurement values can be read in and output as a text file corresponding to the terminal pro-
gram.
To reach 20 meas/s the baud rate must be set to 19200 baud in the Setup of the
VOR/ILS Analyzer EVS200. It must be attended the acceptance of the data transfering
rate by the terminal program.
The measurement can be stopped through the command FA0 (refer to Command
FA0).
Example:
command from the controller response of the VOR/ILS Analyzer EVS200
input: FA2 <CR>
fa2 <CR>
With the command FA2 the echo
mode is automatically switched
OFF.
output form: (DDM <CR >, RF level <CR >,
AM90 <CR >, AM 150 <CR >)
DDM: four-digit with indication (dimensionless)
example: -1000 <CR > (-0.1000 DDM)
five-digit with indication (
µ
A)
example: -09890 <CR > (-98.90
µ
A )
RF level: three-digit with indication (dBm)
example: -400 <CR > (-40.0dBm)
122 <CR > (12.2dBm)
Modulation depth: three-digit (%)
example: 202 <CR > (20.2 %)
004 <CR > (0.4 %)
1/90Hz = 11.1msec.
DSP-Analysis
DATA-Transfer
DDM, AM90, AM150,
RF-Level - Calculation
RS232-
Transfer
TXD-Signal
fromEVS200
40 msec. 10 msec.
DATA-Transfer
DDM, AM90, AM150,
RF-Level - Calculation
RS232-
Transfer
DATA-Transfer
N N+1 N+2 N+3 N+4 N+5 N+6 N+7 N+8 N+9 N+10
N N+4