Brandywine NFS-220 User manual

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MANUAL P/N 900000111 REVK
User Guide
Networked Frequency Standard
Model NFS-220
P/N 091000001
Revision K
April 2018
Brandywine Communications
1153 Warner Ave
Tustin, CA 92780
[phone]
[phone]
http://www.brandywinecomm.com

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MANUAL P/N 900000111 REVK
Revision History
REVISION
DATE
COMMENTS
NC
8-13-2008
Original release of NFS220 user guide.
A
02-20-2009
Updated
B
02-19-2010
Change Alarm Status on J9 INPUT/OUTPUT
C
05-20-2011
Update to reflect updated web pages. Incorporated Free run mode
D
12-11-2013
Updated to add firmware and FPGA update procedures
E
01-24-2014
Updated to include power consumption.
F
08-22-2014
Updated to include default IP address information.
G
05-29-2015
Added factory default instructions
H
09-04-2015
Added MIB Description
J
12-15-2015
Corrected information about pulse width
K
04-03-2018
Clarified IRIG local time settings, updated Java installation instructions.

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MANUAL P/N 900000111 REVK
Safety Warnings
WARNING: This unit contains lethal AC voltages. Disconnect the unit from
the AC supply before removing the cover.
WARNING:
The lightning flash with an arrowhead inside of an equilateral triangle is intended to alert the
user to the presence of un-insulated “dangerous voltage” within the product’s enclosure. The
“dangerous voltage” may be of sufficient magnitude to constitute a risk of electrical shock to
people. Do not attempt to repair the unit without first unplugging it.
CAUTION:
The exclamation point inside of an equilateral triangle is intended to alert the user to the
presence of important operation and maintenance instructions in the user guide. This unit
should only be repaired by qualified personnel. Several board assemblies contain static
sensitive devices. Appropriate procedures must be used when handling these board
assemblies.

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MANUAL P/N 900000111 REVK
Table of Contents
1!Introduction.....................................................................................................................................6!
2!Specifications .................................................................................................................................7!
2.1!LED Indicators.......................................................................................................................10!
2.2!Connections..........................................................................................................................11!
2.3!Source Impedance Selection and Signal Termination.........................................................12!
3!Unpacking and Installation ...........................................................................................................13!
3.1!Unpacking.............................................................................................................................13!
3.2!Installation.............................................................................................................................13!
3.2.1!Mounting........................................................................................................................13!
3.2.2!Power.............................................................................................................................13!
3.2.3!Ethernet.........................................................................................................................13!
3.2.4!Input Reference Connections........................................................................................13!
3.2.4.1!GPS Antenna .........................................................................................................13!
3.2.4.2!External GPS Receiver (Have Quick/1PPS)..........................................................15!
3.2.4.3!External 1PPS Receiver.........................................................................................15!
3.2.5!NTP Server Connection Example..................................................................................16!
3.3!Output signal connections.....................................................................................................16!
3.3.1!Signal Connections........................................................................................................16!
3.3.2!Network Connections.....................................................................................................16!
3.3.2.1!Discovering the automatically assigned NFS-220 IP address................................16!
3.3.2.2!Changing NFS220 Network IP address using Internet Explorer............................17!
3.3.2.3!Latest Version of Java Software.............................................................................19!
4!Configuration................................................................................................................................20!
4.1!Setup.....................................................................................................................................20!
4.1.1!System...........................................................................................................................20!
4.1.2!IP Address.....................................................................................................................21!
4.1.3!SNMP Download MIB File.............................................................................................21!
4.2!Status....................................................................................................................................23!
4.2.1!Local Time.....................................................................................................................23!
4.2.2!Reference Status...........................................................................................................23!
4.2.3!Oscillator Status.............................................................................................................24!
4.2.4!Fault Status....................................................................................................................24!
4.3!Time......................................................................................................................................25!
4.3.1!Serial Output (TOD).......................................................................................................26!
4.3.2!Time Zone Settings........................................................................................................27!
4.3.2.1!Standard Time Zone settings.................................................................................27!
4.3.2.2!Special case – 30 minute time zone setting...........................................................27!
4.3.3!Daylight Saving Time.....................................................................................................28!
4.3.4!Daylight Saving Time (Advanced) .................................................................................28!
4.3.5!Setting the IRIG Time Code format. ..............................................................................29!
4.4!Password ..............................................................................................................................30!
4.4.1!Password.......................................................................................................................30!
4.5!Reference..............................................................................................................................31!
4.5.1!Reference Selection ......................................................................................................32!
4.5.1.1!GPS Reference (Factory default)...........................................................................32!

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MANUAL P/N 900000111 REVK
4.5.1.2!Have Quick & 1PPS Reference..............................................................................33!
4.5.1.3!External 1PPS Only Reference..............................................................................33!
4.5.1.4!Free-Run Reference...............................................................................................33!
4.5.2!10 MHz Output Level Settings......................................................................................34!
4.5.3!Output Timing Setting....................................................................................................35!
4.5.3.1!Setting 1PPS Pulse width.......................................................................................35!
4.5.3.2!Setting 1PPS Pulse delay ......................................................................................36!
4.6!Help.......................................................................................................................................37!
4.7!Firmware Upgrade ................................................................................................................37!
4.8!FPGA Upgrade......................................................................................................................38!
4.9!Webpage Upgrade................................................................................................................40!
5!Drawings.......................................................................................................................................45!
6!Link Settings.................................................................................................................................48!
7!Appendix A – Serial Output for firmware version ###...................................................................50!
8!Appendix B – MIB File..................................................................................................................52!
Table of Figures
Figure 1 Typical NFS-220 NTP Server Network Connection..............................................................16!
Figure 2 NFS-220 console port start-up string....................................................................................17!
Figure 3 Browser settings for NFS-220...............................................................................................17!
Figure 5: Setup...................................................................................................................................20!
Figure 6 Download MIB file.................................................................................................................21!
Figure 7 NFS-220 MIB (sample).........................................................................................................22!
Figure 8: Status...................................................................................................................................23!
Figure 9: Time.....................................................................................................................................25!
Figure 10 Standard IRIG Formats.......................................................................................................29!
Figure 11: Password...........................................................................................................................30!
Figure 12 Reference Tab....................................................................................................................31!
Figure 13 Selecting the NFS-220 reference .......................................................................................32!
Figure 14 GPS Fixed/Mobile Selection...............................................................................................32!
Figure 15 Manual Setting of Time in NFS-220....................................................................................33!
Figure 16 Manual Setting of Time in NFS-220....................................................................................34!
Figure 17 Setting NFS-220 10 MHz output level ................................................................................35!
Figure 18 Output Timing Settings.......................................................................................................35!
Figure 19 - Serial Time, Position and Velocity output.........................................................................47!

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MANUAL P/N 900000111 REVK
1Introduction
The NFS220 is a precision time and frequency standard that uses the Global Positioning System (GPS).
It is designed for use in WI-FI, Wi-Max, satellite communications, telecommunications and military
communication applications.
The NFS220 utilizes a high performance 16 channel GPS receiver. An automatic position-averaging feature
enables the best use of GPS when operating in a fixed location.
The NFS220 is fitted with an internal back up oscillator that is continuously calibrated to GPS using an
advanced algorithm, providing optimal frequency control of the oscillator. This ensures that the highest time
and frequency accuracy is maintained if no satellites can be tracked, and ensures an ultra stable, low noise
frequency reference.
The basic NFS220 includes a precision OCXO frequency standard, while TCXO and Rubidium oscillators
are available options that offer a variety of price and performance options. An option with a low noise OCXO
phase locked to a Rubidium is also available, combining the low noise characteristic of the OCXO with the
long term stability of a Rubidium oscillator.
The NFS220 provides “at a glance” status indication via front panel LED’s and can be integrated with other
management systems using Ethernet and serial ports.
The NFS220 provides simple integration into military platforms by allowing synchronization from Have Quick
time code, which is available on military SA-ASM GPS receivers such as the DAGR(AN/PSN-13) or
PLGR(AN/PSN-11). The NFS220 also generates Have Quick and 1PPS signals compatible with ICD-GPS-
060.
The integrated Ethernet interface provides Network Time Protocol (NTP) synchronization to other connected
computers. In addition to NTP, the NFS220 Ethernet interface contains a built-in web server that allows the
NFS220 to be controlled using a standard web browser such as Internet Explorer or Chrome. Simple
Network Management Protocol (SNMP) allows easy integration of the NFS220 with industry standard
network management systems.
The NFS220 provides three 1PPS time mark outputs. A unique feature allows precise controlled delays to
be inserted into these outputs to compensate for cable- and other propagation delays. Compensation delay
is independent for each output and has <1ns resolution.
Serial time code outputs are provided to allow time synchronization to be distributed to computers, displays,
and other equipment requiring precision time. Two outputs are dedicated to Have Quick time code. Two
outputs (one modulated, one DC level shift) may be user selected from IRIG A, IRIG B, IRIG E or IRIG G.
Four low phase noise 10 MHz sine wave outputs from the disciplined oscillator are provided. Signal
amplitude is able to be set using the software available.
All outputs are provided with activity detectors. Loss of any output is indicated by means of an individual
front panel alarm LED as well as through the network interface or a discrete alarm output.

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MANUAL P/N 900000111 REVK
2Specifications
Reference Inputs
GPS
Receiver Type
Parallel 16 Channel. All-in-view satellites tracked continuously and
simultaneously
Satellite Signal
GPS L11575.42 MHz
Satellite Code
C/A 1.023 MHz
Warm Start
<10 sec(Open Sky)
Autonomous Start
<60 seconds Cold Start (Open Sky)
Cold Start Requirement
Automatic: No input of time or position required
Position Accuracy
2.4 m horizontal, 5 m altitude with respect to WGS84 after 24 hourposition
averaging
Antenna Connector
BNC Female
Have
Quick
Signal Type
Have Quick II per ICD-GPS-060
Input Impedance
50 ohm
Level
0-5V
TFOM Threshold
4
Connector
DB-9 (J-10)
External
1PPS
Signal Type
1PPS
Input Impedance
50 ohm
Level
2.5 - 5V
Maximum Frequency
Error
2x10-9
Connector
DB-9 (J10)
Input Modes
GPS
Default
Have Quick/1PPS
Uses 1PPS for synchronization, Time of Day is loaded automatically from
Have Quick
External 1PPS only
Uses 1PPS for synchronization, Time of Day is loaded manually by user
System Accuracy
Specifications are based on GPS mode tracking satellites unless noted.
Timing Accuracy
±100 ns. absolute UTC
Std Deviation 15ns (OCXO)
Timing Accuracy
(holdover mode, ± 5ºC)
< 25 µsec/day (OCXO)
< 2 µsec /day (Rb2)
Frequency stability)
See tables below
Oscillator Option
Stability
-10 to 50 °C
Allan Variance
1s
10s
100s
1000s
10000s
1 day
TCXO
2.5x10-6
1x10-7
1x10-7
1x10-7
5x10-8
2x10-9
1x10-11
OCXO (std)
3x10-9
5x10-12
8x10-12
1x10-11
1x10-11
5x10-12
1x10-12
Rb1
7x10-10
3x10-11
1.6x10-11
8x10-12
<1x10-12
Rb2
4x10-10
1x10-11
3x10-12
1x10-12
<1x10-12
Rb/OCXO
4x10-10
5x10-12
1x10-11
3x10-12
<1x10-12

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MANUAL P/N 900000111 REVK
System Outputs
1PPS Output
3 Outputs
Connector
BNC (2) DB9 (1)
Level
0-10V for output 1 and 2 (BNCs)
0-5V for output 3 (DB9)
On Time
Rising Edge
Width
100ns to 6.5 ms software settable in 100ns steps
Delay
-0.5 to +0.5 seconds in 1 ns steps
Individually settable for each output
Network Interface
Interface Type
10BaseT, Half-Duplex.
Protocols
TCP/IP, UDP, NTPv3, HTTP, SNMP v1, DHCP
Serial Interface
Type
RS232
RS422 link selectable by user
Baud rate
115200, N,8,1
Sine Wave Outputs
Outputs
4 independently buffered outputs with software leveladjustment
Connector
BNC
Frequency
10MHz
Level
9-16dBm into 50 ohm
Software settable
Phase Noise (OCXO,
RB/OCXO)
Offset dBc/√/Hz
1Hz -90
10Hz -120
100Hz -130
1kHz -140
10kHz -150
100kHz -155
Time Code 1 Output
(Modulated)
Connector
BNC
Code Type
IRIG A135, B125, E115, G145 software selected
Control
Functions
IEEE 1344
Level
3 V p-p into 600 ohm
Time Code 2 Output
(DCLS)
Connector
DB9 J9-2
Code Type
IRIG A005, B005, E005, G005
Selection
same as modulated code
Levels
DC Level Shift (0-5V)
Time Code 3,4 Output
Connector
BNC (1) DB9 (1)
Code Type
Have Quick
per ICD-GPS-060
Levels
0-10V for output 1 (BNC)
0-5V for output 2 (DB9)
Alarm Status
Voltage free relay changeover contacts. Link settable for+5V alarm out
Status Indicator LED’s
Power
Tracking Satellites
Valid Time

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MANUAL P/N 900000111 REVK
Holdover/12hr Holdover alarm
Output Good/Fail ( 8 LEDs)
Environmental
Temperature
Instrument: -10 to +50 °C
Antenna: -40 to +85 °C
Humidity
95% non condensing
Power
Consumption
85-265VAC 50/60Hz
40 Watts
Optional
12VDC, 24VDC, -48VDC, 125VDC
Dimensions
19” rack mount
1.75” (1U) height, 6.5“ depth
Weight
3.5 lb. typical
EMC Emission
EN55022
FCC Chapter 15 Subpart B, Class A
EMC Immunity
EN55024

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MANUAL P/N 900000111 REVK
2.1 LED Indicators
Table 1below describes each LED indicator on the front panel of the NFS-220.
LED
COLOR
COMMENT
Power
Green
Indicates Prime Power is applied to the NFS220.
Time Valid
Green
Indicates that the unit has been synchronized to an external reference.
Amber
Indicates that the unit is in Holdover.
Tracking
Satellites
Green
Indicates that the GPS receiver is tracking satellites OR that the Have
Quick time code has been successfully decoded if HQ is selected as a
reference.
Red
Indicates that the NFS220 has not had a valid reference for 12 hours.
Off
Indicates that the NFS220 is not tracking satellites or successfully
decoding HQ.
IRIG
J8
Green
Indicates that the IRIG time code output on J8 is operating.
Red
Indicates that the IRIG time code output on J8 has failed or that there
is an excessive load on the output.
HQ
J7
Green
Indicates that the Have Quick time code output on J7 is operating.
Red
Indicates that the Have Quick time code output on J7 has failed or that
there is an excessive load on the output.
1PPS
J6
Green
Indicates that the 1PPS pulse output on J6 is operating.
Red
Indicates that the 1PPS pulse output on J6 has failed or that there is
an excessive load on the output.
1PPS
J5
Green
Indicates that the 1PPS pulse output on J5 is operating.
Red
Indicates that the 1PPS pulse output on J5 has failed or that there is
an excessive load on the output.
10MHz
J4
Green
Indicates that the 10MHz output on J4 is operating.
Red
Indicates that the 10MHz output on J4 has failed, that there is an
excessive load on the output,or that the output is connected to a
cable that is improperly terminated and is causing a reflection on the
line.
10MHz
J3
Green
Indicates that the 10MHz output on J3 is operating.
Red
Indicates that the 10MHz output on J3 has failed, that there is an
excessive load on the output,or that the output is connected to a
cable that is improperly terminated and is causing a reflection on the
line.
10MHz
J3
Green
Indicates that the 10MHz output on J2 is operating.
Red
Indicates that the 10MHz output on J2 has failed, that there is an
excessive load on the output,or that the output is connected to a
cable that is improperly terminated and is causing a reflection on the
line.
10MHz
J3
Green
Indicates that the 10MHz output on J1 is operating.
Red
Indicates that the 10MHz output on J1 has failed, that there is an
excessive load on the output,or that the output is connected to a
cable that is improperly terminated and is causing a reflection on the
line.
Ethernet
J11
Yellow
Activity
Green
Link
Table 1 LED Indicators