Specifications

MDS 05-3438A01, Rev. E MDS 4790/9790 Series Installation and Operation Guide I-3
RF forward output power (PWR command) 47
RX timeout (RX Timeout screen) 67
signal-to-noise ratio (S/N Ratio screen) 74
signal-to-noise ratio (SNR, SNR! commands) 51
soft carrier de-key delay (SCD command) 50
soft carrier de-key delay (Soft Carrier De-Key Delay
screen) 67
software release information (Software Revision screen) 74
software release information (SREV command) 52
start of new message timer (DMGAP command) 42
time (Set Time screen) 73
time (TIME command) 54
transmit audio level (TXLEVEL command) 55
transmit frequency (Transmit Frequency screen) 64
transmit frequency (TX command) 54
transmit level (Transmit Level screen) 70
transmit timeout (Transmit Timeout screen) 67
transmit timeout duration (Transmit Timeout Duration
screen) 67
transmitter state (Manual Key screen) 68
transmitter state (Transmitter Status screen) 74
Display Contrast screen 71
DKEY command (deactivate transmitter). See also KEY
command 41
DLINK command
enable/disable network-wide diagnostics, description 41
use of 80
DMGAP command (set time to wait between characters) 42
DTYPE command
set radio to root or node for diagnostics, description 42
use of 80
E
Emphasis
enable/disable (Emphasis screen) 66
Emphasis screen 66
Enable/disable
audio transmit boost (Transmit Gain screen) 71
continuous keying (CKEY command) 40
data buffering (Data Buffering screen) 70
emphasis and de-emphasis (Emphasis screen) 66
internal RTU (RTU command) 48
network-wide diagnostics (DLINK command) 41
network-wide diagnostics, procedures 80
receive attenuator (Receive Pad screen) 71
receive attenuator (RXPAD command) 50
repeater operation (REPEATER command) 48
transmit audio boost (TXGAIN command) 55
transmit timeout timer (Transmit Timeout screen) 67
ENTER button
use in display-only mode 58
use in radio configuration 59
ESCAPE button
use in display-only mode 58
use in radio configuration 60
Event codes 53
major alarms, defined 79
minor alarms, defined 79
Event log
use in problem solving 78
Event Log screen 75
F
Fade margin
discussion 97
Fading, calculating probability of system 99
Feedline
installing 17
loss chart 10
selection 9
Formulas 98–99
free space path loss 98
Fresnel zone boundary 98
probability of system fading 99
theoretical signal strength 98
Frequency
in simplex or switched carrier operation 4
preventing unnecessary use of (Transmit Timeout
screen) 67
range 93
receiver range 94
receiver stability 95
set/display receive (Receive Frequency screen) 65
set/display receive (RX command) 49
set/display transmit (Transmit Frequency screen) 64
set/display transmit (TX command) 54
stability 94
step size 93
transmitter range 94
Fresnel zone
boundary, formula 98
clearance 96
obstructions, illustrated 96
Front panel
controls, illustrated 58
ENTER button 58
ESCAPE button 58
illustrated 26
indicators 25
LCD display 27
left/right arrow buttons 58
removing 13
removing or re-installing 84
removing, illustrated 85
up/down arrow buttons 58
H
Hardware, display revision level (HREV command) 43
Hexadecimal
alarm code display (Alarm Masks screen) 71
summarize alarms in (ALARM command) 35
use to classify events as major alarms (AMASK
command) 37
use to classify events as major alarms (NMASK
command) 45
values for major alarm conditions 36
HREV command (display hardware revision level) 43
I
I/O ALR LED 27
Illustrations
antenna height vs. theoretical radio horizon 97
Antenna switch module removal 90
audio connections 21
bench test setup 80
data connector 22
DC power supply 14
diagnostics port J1 pin connections 21