Miteq DNB-2B User manual

100 Davids Drive
Hauppauge, New York 11788-2034
Tel: [phone]
Fax: [phone]
www.miteq.com
OPERATION AND
MAINTENANCE MANUAL
MULTIBAND BLOCK DOWNCONVERTERS
The model number supplied is:
______ DNB-2B
______ DNB-3B
______ DNB-3B-1
The MITEQ reference number is:
Revision B
5/04

2
MANUAL REVISIONS
5/7/04: REV.A TO REV.B
ADDED SECTION 3.7 AND SUBSECTIONS 3.7.1, 3.7.2, 3.7.3, 3.7.4, APPENDICES
AND GLOSSARY - ETHERNET INTERFACE INSTALLATION AND
OPERATION
UPDATED SECTION 3.2.1 TO INCLUDE ETHERNET INFORMATION
REVISED TABLE OF CONTENTS TO INCLUDE AFFORMENTION CHANGES

3
TABLE OF CONTENTS
SECTION 1
INTRODUCTION
Paragraph Page
1.1 GENERAL DESCRIPTION................................................................................ 7
1.1.1 PHYSICAL.............................................................................................. 7
1.1.2 FUNCTIONAL ........................................................................................ 8
1.1.3 MODEL NUMBERS............................................................................... 8
Converter Model Numbers..................................................................... 8
1.2 EQUIPMENT CHARACTERISTICS.................................................................. 9
1.2.1 PHYSICAL.............................................................................................. 9
Connector Wiring Information................................................................ 9
1.2.2 FUNCTIONAL ........................................................................................ 10
SECTION 2
INSTALLATION
2.1 UNPACKING, STORAGE, RESHIPMENT........................................................ 13
2.2 MOUNTING ...................................................................................................... 13
2.3 TURN-ON PROCEDURE.................................................................................. 13
SECTION 3
OPERATION
3.1 CONTROLS....................................................................................................... 15
3.1.1 EXTERNAL CONTROLS....................................................................... 15
AC Power............................................................................................... 15
Fuse ...................................................................................................... 15
3.1.2 INTERNAL CONTROLS........................................................................ 15
Power Supply Output Voltage Adjustment............................................ 15

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TABLE OF CONTENTS (Cont.)
SECTION 3
OPERATION
Paragraph Page
3.2 FRONT PANEL OPERATIONS......................................................................... 15
3.2.1 KEYPAD OPERATION.......................................................................... 16
Menu Key............................................................................................... 16
Cursor Key............................................................................................. 16
Data Entry Keys..................................................................................... 16
3.2.2 MAIN MENU........................................................................................... 17
3.2.3 ALARM MENU....................................................................................... 19
3.2.4 REMOTE OPERATION MENU.............................................................. 21
3.2.5 AUXILIARY MENU................................................................................. 23
3.2.6 UTILITY MENU...................................................................................... 23
3.2.7 UNIT TITLE MENU................................................................................ 24
3.3 REMOTE OPERATION...................................................................................... 25
3.4 SERIAL REMOTE PROTOCOL (RS485/RS422/RS232)................................. 25
3.4.1 SERIAL MESSAGE FORMAT............................................................... 25
3.5 IEEE-488 MESSAGE PROTOCOL................................................................... 27
3.5.1 IEEE-488 MESSAGE FORMAT ............................................................ 27
3.6 COMMAND CODE SUMMARY......................................................................... 28
3.6.1 COMMAND CODES.............................................................................. 28
3.6.2 ERROR CODES (SERIAL PROTOCOL ONLY) ................................... 28
3.6.3 SYSTEM FAULT STATUS = ALR......................................................... 29
3.6.4 UNIT ATTENUATION = ATT................................................................. 29
3.6.5 FREQUENCY BAND INFORMATION = BND....................................... 30
3.6.6 INTERNAL CALENDAR/CLOCK = CLK ............................................... 30
3.6.7 UNIT COMBINATION COMMAND = COM........................................... 31
3.6.8 EXTERNAL ALARM CONFIGURATION = EAC................................... 31
3.6.9 LO FREQUENCY = FRQ....................................................................... 32
3.6.10 ALARM LOG = LOG.............................................................................. 32
3.6.11 UNIT MEMORY REGISTER STORE/RECALL = MEM........................ 33
3.6.12 UNIT MUTE COMMAND = MUT ........................................................... 34
3.6.13 UNIT NAME = NAM............................................................................... 34
3.6.14 REFERENCE FREQUENCY ADJUSTMENT = REF............................ 34
3.6.15 FIRMWARE TITLE AND REVISION = REV.......................................... 35
3.6.16 UNIT MEMORY REGISTER STORE/RECALL AND SET = SET........ 35
3.6.17 UNIT STATUS = STA (SERIAL PROTOCOL ONLY)........................... 36
3.6.18 USER TITLE = USR............................................................................... 37
3.6.19 SYSTEM VOLTAGES = VLT................................................................. 37
3.6.20 EXAMPLES............................................................................................ 37
3.6.21 IEEE-488 SERVICE REQUEST............................................................ 38

5
TABLE OF CONTENTS (Cont.)
SECTION 3
OPERATION
Paragraph Page
3.7 ETHERNET INTERFACE INSTALLATION AND OPERATION........................ 39
3.7.1 FUNCTIONAL DESCRIPTION.............................................................. 39
3.7.2 INSTALLATION...................................................................................... 39
3.7.3 ACCESSING THE SYSTEM.................................................................. 40
3.7.4 FIRMWARE UPGRADE......................................................................... 43
SECTION 4
PRINCIPLES OF OPERATION
4.1 INTRODUCTION................................................................................................ 47
4.2 FUNCTIONAL DESCRIPTION.......................................................................... 47
4.2.1 DOWNCONVERTER FUNCTIONAL DESCRIPTION........................... 47
4.2.2 BLOCKDIAGRAMS............................................................................... 48
4.2.3 FREQUENCY PLANS............................................................................ 48
4.3 MAJOR SUBASSEMBLIES FUNCTIONAL DESCRIPTION............................. 49
4.3.1 DOWNCONVERTER RF MODULE (A2A1).......................................... 49
4.3.2 OUTPUT MODULE (A2A3).................................................................... 49
4.3.3 CRYSTAL OSCILLATOR (A3A1).......................................................... 50
4.3.4 LOCAL OSCILLATOR (A3A2)............................................................... 50
4.3.5 POWER SUPPLY (A1A1)...................................................................... 51
4.3.6 CONTROL BOARD/FIRMWARE KIT (A4A1)........................................ 51
4.3.7 FAN (A1A2)............................................................................................ 51

6
TABLE OF CONTENTS (Cont.)
SECTION 5
MAINTENANCE
Paragraph Page
5.1 PREVENTIVE MAINTENANCE......................................................................... 52
5.1.1 DC VOLTAGE........................................................................................ 52
5.1.2 GAIN OF THE CONVERTER................................................................ 52
5.1.3 FREQUENCY MEASUREMENT ........................................................... 52
5.2 CORRECTIVE MAINTENANCE........................................................................ 52
5.3 CHANGING THE REMOTE INTERFACE FROM RS485/422 TO RS232 OR
FROM RS232 TO RS485/422........................................................................... 53
5.3.1 INSTALLING A NEW CONTROL BOARD/FIRMWARE KIT (A4A1).... 54
LIST OF DIAGRAMS
Figure 1-1 Front Panel, Frequency Converter.............................................................. 7
Figure 1-2 Real Panel, Frequency Converter............................................................... 7
Figure 3-1 Internal Power Supply Adjustment.............................................................. 15
Figure 4-1 Downconverter Functional Block Diagram.................................................. 48

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SECTION 1
INTRODUCTION
1.1 GENERAL DESCRIPTION
1.1.1 PHYSICAL
Figure 1-1. Front Panel, Frequency Converter
Figure 1-2. Rear Panel, Frequency Converter
RFIF
REMOTE (J6)
ALARM (J3)
0I

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1.1.2 FUNCTIONAL
The MITEQ Multi-band Block Converters are designed for advanced satellite communications
systems. Both upconverters and downconverters are available for a wide variety of frequency
conversion scenarios. Phase noise, amplitude flatness, group delay and spurious outputs have
been optimized to provide the user with a transparent frequency conversion for all video and
data applications.
A strong feature set of monitor and control functions supports powerful local and remote control.
Among the features are control of frequency, attenuation, and 64 memory locations for each
converter where various setups can be stored and recalled easily. Also, a log is continuously
updated with time stamped records of activity for each converter. The equipment can operate
stand-alone or can be arranged in a redundancy configuration without the need for a dedicated
switch control unit.
1.1.3 MODEL NUMBERS
Converter Model Numbers
Multi-band Block Downconverters
Model Number Band Input band Output band
DNB-3B Band 1 10.7-11.45 GHz 0.95-1.7 GHz
Band 2 11.45-12.2 GHz 0.95-1.7 GHz
Band 3 12.2-12.75 GHz 0.95-1.5 GHz
DNB-3B-1 Band 1 10.95-11.7 GHz 0.95-1.7 GHz
Band 2 11.7-12.2 GHz 0.95-1.45 GHz
Band 3 12.2-12.75 GHz 0.95-1.5 GHz
DNB-2B Band 1 10.7-11.75 GHz 0.95-2.0 GHz
Band 2 11.7-12.75 GHz 0.95-2.0 GHz

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1.2 EQUIPMENT CHARACTERISTICS
1.2.1 PHYSICAL
Weight.................................................................................................................18 pounds nominal
Chassis Dimensions..........................................................................19” x 20” x 1.75” panel height
RF connectors................................................................................................................SMA female
RF Monitor connector....................................................................................................SMA female
IF Connectors......................................................................................................................N female
IF Monitor connector..................................................................................................... SMA female
LO Monitor connectors..................................................................................................SMA female
Alarm connector......................................................................................................................DE-9P
Remote interface connector
RS485, RS422, RS232......................................................................................................DE-9S
IEEE-488.....................................................................................................IEEE-488 receptacle
Primary power input connector..............................................................................................IEC320
Connector Wiring Information
Alarm Connector (J3)
Function Pins Normal Fault
Summary Alarm 4,5 Open Closed
Summary Alarm 5,6 Closed Open
Redundancy Alarm 1,2 Open Closed
Redundancy Alarm 2,3 Closed Open
External Alarm Input 7,8 User defined
Remote Interface Connector (J6)
RS485 and RS422 RS232
Pin Designation Pin Designation
1Ground 2RCV Data
3Data Out - 3Tx Data
5Data In - 5Ground
7Data Out + 7RTS
9Data In + 8CTS

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1.2.2 FUNCTIONAL
Converter Performance Specifications
Type Single conversion
Frequency step size See Model Number Table
Frequency sense No inversion
Model Number Band Input band Output band
DNB-3B Band 1 10.7-11.45 GHz 0.95-1.7 GHz
Band 2 11.45-12.2 GHz 0.95-1.7 GHz
Band 3 12.2-12.75 GHz 0.95-1.5 GHz
DNB-3B-1 Band 1 10.95-11.7 GHz 0.95-1.7 GHz
Band 2 11.7-12.2 GHz 0.95-1.45 GHz
Band 3 12.2-12.75 GHz 0.95-1.5 GHz
DNB-2B Band 1 10.7-11.75 GHz 0.95-2.0 GHz
Band 2 11.7-12.75 GHz 0.95-2.0 GHz
Input characteristics
Frequency See Above Table
Impedance 50 Ohms
Return loss 20 dB minimum
Signal monitor -20 dBc nominal
LO Leakage -80 dBm maximum
Input level (non-damage) +20 dBm maximum
Output characteristics
Frequency See Above Table
Impedance 50 Ohms
Return loss 18 dB minimum
Signal monitor N/A
Power output at 1 dB
compression point +10 dBm minimum
Transfer characteristics
Gain +30 dB minimum
Noise Figure 15 dB
Image rejection 80 dB minimum
Level stability ±0.25 dB/day at constant temperature
Amplitude response ±0.5 dB/80 MHz
±1.0 dB over any band
Group delay 1 ns over any band typical
Intermodulation distortion
(third order) With two 0 dBm output signals, 40 dBc minimum
AM/PM conversion 0.1°/dB maximum up to 0 dBm output
Spurious outputs
Signal related 60 dBc up to 0 dBm output
Signal independent -75 dBm maximum
Gain adjustment 30 dB in 0.2 dB steps
Frequency stability
Standard ±2 x 10-8, 0 to 50°C
±5 x 10-9/day typical (fixed temperature after 24 hours on time)
Option 10B ±5 x 10-9, 0 to 50°C
1 x 10-9/day typical (fixed temperature after 24 hours on time)
Option 10C ±2 x 10-9, 0 to 50°C
1 x 10-9/day typical (fixed temperature after 24 hours on time)

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Converter Performance Specifications (Continued)
Transfer characteristics (Cont.)
External reference 5 MHz or 10 MHz, +4±3 dBm
Unit will automatically switch to internal reference if External
Reference level falls below +1 dBm nominal.
Phase noise See model number table for phase noise table designation
LO Monitors -5 dBm to –15 dBm
Primary power 90-250VAC
Power Consumption 50 Watts nominal
Fuse T1.25A
Environmental (Operating)
Ambient temperature 0 to +50°C
Relative humidity Up to 95% at 30°C
Atmospheric pressure Up to 10,000 feet
Environmental (Non-operating)
Ambient temperature -50 to +70°C
Relative humidity Up to 95% at 40°C
Atmospheric pressure Up to 40,000 feet
Shock and vibration Normal handling by commercial carriers

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TABLE 2
Offset (Hz) 10 100 1K 10K 100K 300K 1M Offset (Hz)
Typical Phase
Noise (dBc/Hz) -50 -70 -87 -92 -95 -95 -115 Maximum Phase Noise (dBc/Hz)
(1.0 Hz Bandwidth)
Straight line curve defined
by the points in the table.
TABLE 1
PHASE NOISE CHARACTERISTICS (1.0 Hz BANDWIDTH)
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
10 100 1,000 10,000 100,000
FREQUENCY OFFSET FROM CARRIER (Hz)
PHASE NOISE (dBc/Hz)
INTELSAT
IESS-308/309
Typical MITEQ
Performance

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SECTION 2
INSTALLATION
2.1 UNPACKING, STORAGE, RESHIPMENT
Carefully open the shipping container and remove the equipment. Inspect the equipment
thoroughly and report any damage.
If the equipment is to be stored, it should be wrapped in plastic and kept in a clean, dry place.
If the equipment is to be reshipped for any reason, wrap in heavy plastic and ship in a heavy
(275 lb. test) double wall carton. At least three inches of a solid packing material should be
used on all sides of the unit. The carton should be marked to indicate that it contains fragile
electronic equipment.
2.2 MOUNTING
THIS EQUIPMENT IS NOT FOR USE IN A DOMESTIC ENVIRONMENT.
THIS EQUIPMENT IS INTENDED FOR RACK MOUNTING.
OPERATOR INJURY MAY OCCUR IF UNIT IS NOT PROPERLY MOUNTED.
THIS EQUIPMENT MUST BE SECURELY MOUNTED.
Slides are provided for mounting in a standard 19" equipment rack.
2.3 TURN-ON PROCEDURE
After mounting, make all external connections per Table 2-1.
Apply power to the equipment using the power On/Off switch.
Allow 20 minutes for warmup of the internal crystal oscillator reference. The unit should be left
in the power-on state for 24 hours in order to reach the specified performance for frequency
stability.
System is now operational.

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Table 2-1. External Connections
DESIGNATION DESCRIPTION
Ground Lug Connect the Ground Lug on the rear panel of the equipment to the
Protective Earth connection of the building.
Power Cord Attach the power cord to the rear panel AC power inlet. Connect the
other end to the power source. Refer to national wiring standards for
the correct connection to the power source.
Alarm Connector (J3) This connector is a form-c contact closure indicating the summary
alarm status of the equipment. See Paragraph 1.2.1 for wiring
information.
Remote Connector
(J6) The Remote Interface connector is an optional connection. This allows the operator to monitor and control the equipment from a remote
location. See Paragraph 1.2.1 for wiring information.
RF Input Connect the RF Input to J1 of the unit.
IF Output Connect the IF Output to J2 of the unit.

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SECTION 3
OPERATION
3.1 CONTROLS
3.1.1 EXTERNAL CONTROLS
For a description of the front panel keys and select switches see Paragraph 3.2.1.
AC Power
Use the rear panel power on/off switch to control AC power to the unit.
Fuse
The fuse is accessible from the top cover of the unit, near the rear panel, in the corner where
the AC input is located. The fuse value is T1.25A.
3.1.2 INTERNAL CONTROLS
Power Supply Output Voltage Adjustment
Power supply voltages are adjusted from potentiometers located on the power supply.
Adjustment should be made using an insulated tuning tool. Voltage tolerances are +5.3 ± 0.2V,
+5.3 ± 0.2V and +15.3 ± 0.25V. There is no adjustment for the –15.3V output.
Figure 3-1. Internal Power Supply Adjustment
3.2 FRONT PANEL OPERATIONS
A Liquid Crystal Display (LCD) and Light Emitting Diode (LED) indicators have been organized
such that important information is available at a glance. The keyboard is divided into functional
groups to allow an operator to easily change any parameter from the front panel. See Figure 1-
1 for the physical layout of the front panel.
The green “POWER” LED is lit when power is on.
The red “ALARM” LED indicates an active alarm. The alarm LED lights amber when no alarms
are active but alarms have been recorded in the log. This LED does not light when no alarms
are active and the log has been cleared.
The green “REMOTE” LED is lit when the unit is under remote control and is off while the unit is
under local control.
POWER SUPPLY
ADJUSTMENT POTENTIOMETERS
AND TEST POINTS
MITEQ # 135782
+15.3V +5.3V "A" +5.3V "B"

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3.2.1 KEYPAD OPERATION
The keypad includes two keys that are for menu navigation, a “MENU” key and a “CURSOR”
key. A full set of numeric Data Entry keys, including up and down arrows, simplify operator
entries. A beeper will sound to acknowledge each key press. An error tone will sound for illegal
entries.
While in Remote mode, local data entry is prohibited. However, all system parameters can be
examined.
After one minute of idle time the display will default to the Main.
Menu Key
The “MENU” key allows the operator to switch the context of the LCD between various menus
with ease. This key provides instant access to all pertinent data in both Local and Remote
modes. Sequential menu key actions will show the menus in the following order:
•Main
•Alarm
•Remote
•Auxiliary
•Utility (Time, Date, and contrast control)
•Unit Title
Cursor Key
The ”CURSOR” key cycles through each of the data fields in a given menu. This accommodates
the simple activation of a field within a menu for data entry.
Data Entry Keys
The Data Entry keys allow the operator to enter specific data into an active field. Data is
entered by using the numeric keypad and pressing “ENT”, or by using the up and down arrows
to scroll until the desired setting is displayed and then pressing the “ENT” key. If using the arrow
keys to change attenuation settings, the “ENT” key need not be pressed. Invalid entries will be
ignored and cause an error tone to sound. Any data entry not terminated by pressing the “ENT”
key will expire after ten seconds, an error tone will sound, and the display will be restored to its
prior setting.

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3.2.2 MAIN MENU
If not already displayed, use the MENU key to access the Main Menu.
The main menu is the default menu at power-up. This menu provides access to the following
parameters of the frequency converter:
•L: LO or Translation Frequency
•I: Input Frequency Band (Factory set and displayed for informational purposes only)
•O: Output Frequency Band (Factory set and displayed for informational purposes only)
•ATT: Attenuation
•Tx or Rx: Mute Status (If Applicable)
•MEM: Memory Registers
•Setup Title (12 Characters)
L: LO Frequency (Translation Frequency)
To change the LO Frequency:
•Press the “CURSOR” key to select the LO Frequency field on the display.
•Use the numeric data entry keys to enter the desired LO Frequency, or the up and down
arrow keys to scan through the valid LO Frequencies.
•Press “ENT” to tune the unit to the desired frequency.
I: Input Frequency Band
The Input Frequency Band that the unit operates at is set at the factory and is displayed for
informational purposes only. This parameter is not user selectable.
O: Output Frequency Band
The Output Frequency Band that the unit operates at is set at the factory and is displayed for
informational purposes only. This parameter is not user selectable.
ATT: Attenuation
To change the attenuation setting of the unit:
•Press the “CURSOR” key to select the attenuation field on the display.
•Use the numeric data entry keys to enter the desired attenuation or the up and down arrow
keys to increment or decrement the attenuation.
•If the numeric data entry keys were used, press “ENT” to set the displayed attenuation.
Tx/Rx: Mute Status (Upconverters) (If Applicable)
The operator can mute the output of the converter as long as the unit is not in an alarm state. If
the unit is in an alarm state, there is no operator override of the Mute. To mute the output of the
converter:
•Press the “CURSOR” key to select the “Tx or Rx” field.
•Use the arrow keys to toggle between ON and MUTE until the desired setting is displayed.
•Press “ENT” to apply the selection.
L:11.250GHz I:12.20-12.75 O: 0.95- 1.50
ATT:26.6dB Rx:MUTE MEM: SETUP

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MEM: Memory Registers
The user can store and recall a combination of LO Frequency, Attenuation and Setup Title in
each of the sixty-four memory locations, 00 through 63. Memory contents can be stored or
reviewed without setting the unit to the parameters indicated in the memory locations.
To store the settings in memory of the unit:
•Press the “CURSOR” key to select the “MEM” field.
•Press either arrow key until “STR” appears in the “MEM” field.
•Press “ENT” to select the store function and the cursor will advance to the memory
register field.
•Use the numeric data entry keys or the up and down arrow keys to select the memory
register (00 through 63) to be updated. The contents of the memory location will be
displayed along with the memory register number. Press “ENT” to select the memory
register field and the cursor will advance to the LO Frequency field.
•Enter the LO Frequency to be stored in the memory location.
•Press the “ENT” key and the cursor will advance to the Attenuation field. This will not
retune the unit. See note below.
•Enter the Attenuation to be stored.
•Press the “ENT” key and the cursor will advance to the Setup Title field. This will not
retune the unit. See note below.
•Use the numeric data entry keys or the arrow keys to enter each character of the Setup
Title to be stored. Use the “CURSOR” key to advance to the next character of the title.
•Press “ENT” to store the entire combination of settings and the cursor will advance to the
“MEM” field. See note below.
•Press “ENT” again to set the unit to the displayed settings.
•If “ENT” is not pressed after ten seconds, or “MENU” is pressed the “MEM” field will
become selected again and the display will be updated to reflect the actual settings.
Note: If “ENT” is not pressed after 10 seconds the display will timeout and the actual setting
stored in the memory register will be displayed. If after 30 seconds “ENT” has not been pressed
the store function will be terminated.
To recall the settings from a memory register:
•Press the “CURSOR” key to select the “MEM” field.
•Press either arrow key until “RCL” appears in the “MEM” field.
•Press “ENT” to select the recall function and the cursor will advance to the memory
register field.
•Use the numeric data entry keys followed by “ENT” or the arrow keys to recall and view
the contents of a memory register (00 through 63) .
•Press “ENT” to set the unit to the retrieved settings.
•If “ENT” is not pressed after ten seconds, or “MENU” is pressed the “MEM” field will
become selected again and the display will be updated to reflect the actual settings.
Setup Title
Setup Title length may be up to twelve characters. The range of allowable characters are ASCII
printable from 32 decimal (SP) to 122 decimal (z). Use the numeric keypad to enter a numeric
digit directly.
To enter a title:
•Press the “CURSOR” key to move the cursor to the Setup Title field. Press an arrow key
or press and hold down the “CURSOR” key to select the first letter in the title field.
•Use the up and down arrow keys or the numeric data entry keys to adjust the character in
this position.
•Press the “CURSOR” key to advance to the next character position.

19
•After all of the desired characters are displayed press the “ENT” key. This will save the
title and truncate any character that may occupy remaining digits.
3.2.3 ALARM MENU
If not already displayed, use the MENU key to access the Alarm Menu.
The alarm menu displays the status of the unit’s alarms. A “Test Alarm” can be set and cleared
from this menu. This menu also allows the operator to review and clear the event log. The
Event Log records the time and dates of significant events including all alarm activity. The
“ALARM” LED on the front panel will light red when there is an Active Alarm. If there are no
Active Alarms, but alarm activity has been stored in the event log, the front panel “ALARM” LED
will light amber.
Active Alarms
The number of active alarms is reported in the alarm menu. To view the alarms:
•Press the “CURSOR” key to highlight the Alarms field on the display.
•Use the arrow keys to scroll through all of the active alarms.
•Press the “MENU” key to return to the Alarm Menu.
Test alarm
The test alarm will cause the status contacts to indicate a fault condition simulating a genuine
alarm. To toggle the state of the Test Alarm:
•Press the “CURSOR” key to highlight the Test Alarm field on the display.
•If the Test Alarm is inactive the field will read “SET TEST ALARM”. If the Test Alarm is
active the field will read “CLEAR TEST ALARM”
•Press the “ENT” key to toggle the state of the Test Alarm.
External Alarm
An external alarm can be sensed by the unit:
•Press the “CURSOR” key to highlight the External Alarm field on the display.
•Use the arrow keys to scroll through three possible settings for the External Alarm Input.
N/A - External Alarm Input is ignored
NO - Normally Open, a closure will indicate a fault
NC - Normally Closed, an open will indicate a fault
•Press the “ENT” key to save the external alarm setting.
2 ALARMS CLEAR TEST ALARM EXT:N/A
32 EVENTS IN THE LOG CLEAR LOG
ACTIVE ALARM 1 OF 2
LOCAL OSCILLATOR ALARM

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Event Log
To view the event log:
•Press the “CURSOR” key to highlight the Event Log field on the display.
•Use the arrow keys to scroll through all of the events stored in the Event Log. Events are
displayed in chronological order with the highest numbered event as the most recent.
•Press the “MENU” key to return to the Alarm Menu.
The events that can be reported are:
•Unit Startup
•+15.3V power supply fault/recovery
•-15.3V power supply fault/recovery
•+5.3V ‘A’ power supply fault/recovery
•+5.3V ‘B’ power supply fault/recovery
•LO fault/recovery
•Frequency change
•Attenuation change
•Unit Mute/Unmute by an operator
•Test Alarm fault/recovery
•Unit Title change
•External fault/recovery
Clear Event Log
To clear the Event Log of its contents:
•Press the “CURSOR” key to highlight the Clear Log field on the display.
•Press the “ENT” key. A message will appear “PRESS ENT TO CLEAR THE EVENT
LOG.”
•Press “ENT” to purge the contents of the event log or Press the “MENU” key to return to
the Alarm menu.
EVENT 1 OF 32 JUN 3 2003 19:53:01
Startup