Spectra EC22S User manual

EPSILONCLOCK
MODEL
EC22S
DUAL
GPS RECEIVER
USER’S MANUAL
95 Methodist Hill Drive
Rochester, NY 14623
Phone: US +1.585.321.5800
Fax: US +1.585.321.5219
3 Avenue du Canada
91974 Les Ulis, France
Phone: [phone]
Fax: [phone]
www.spectracomcorp.com
www.spectracom.fr
Ref. Number 400011-C
Manual Revision C
20 May 2008

Copyright © 2008 Spectracom Corporation. The contents of this publication may not be
reproduced in any form without the written permission of Spectracom Corporation.
Specifications subject to change or improvement without notice.
Spectracom, EPSILON CLOCK, NetClock, Ageless, TimeGuard, TimeBurst, TimeTap,
LineTap, MultiTap, VersaTap, and Legally Traceable Time are Spectracom registered
trademarks. All other products are identified by trademarks of their respective
companies or organizations. All rights reserved.

SPECTRACOM LIMITED WARRANTY
LIMITED WARRANTY
Spectracom warrants each new product manufactured and
sold by it to be free from defects in software, material,
workmanship, and construction, except for batteries, fuses, or
other material normally consumed in operation that may be
contained therein AND AS NOTED BELOW, for five years after
shipment to the original purchaser (which period is referred to
as the “warranty period”). This warranty shall not apply if the
product is used contrary to the instructions in its manual or is
otherwise subjected to misuse, abnormal operations, accident,
lightning or transient surge, repairs or modifications not
performed by Spectracom.
The GPS receiver is warranted for one year from date of
shipment and subject to the exceptions listed above. The
power adapter, if supplied, is warranted for one year from date
of shipment and subject to the exceptions listed above.
THE TIMEVIEW ANALOG CLOCKS ARE WARRANTED FOR
ONE YEAR FROM DATE OF SHIPMENT AND SUBJECT TO
THE EXCEPTIONS LISTED ABOVE.
THE TIMECODE READER/GENERATORS ARE
WARRANTED FOR ONE YEAR FROM DATE OF SHIPMENT
AND SUBJECT TO THE EXCEPTIONS LISTED ABOVE.
THE WIRELESS CLOCK SYSTEM TRANSMITTERS AND/OR
TRANSCEIVERS AND CLOCKS ARE WARRANTED FOR
TWO YEARS FROM DATE OF SHIPMENT AND SUBJECT
TO THE EXCEPTIONS LISTED ABOVE.
THE EPSILON CLOCKS, BOARDS, AND
SYNCHRONIZATION UNITS ARE WARRANTED FOR TWO
YEARS FROM DATE OF SHIPMENT AND SUBJECT TO THE
EXCEPTIONS LISTED ABOVE.
The Rubidium oscillator, if supplied, is warranted for two years
from date of shipment and subject to the exceptions listed
above.
All other items and pieces of equipment not specified above,
including the antenna unit, antenna surge suppressor and
antenna pre-amplifier are warranted for 5 years, subject to the
exceptions listed above.
WARRANTY CLAIMS
Spectracom’s obligation under this warranty is limited to in-
factory service and repair, at Spectracom’s option, of the
product or the component thereof, which is found to be
defective. If in Spectracom’s judgment the defective condition
in a Spectracom product is for a cause listed above for which
Spectracom is not responsible, Spectracom will make the
repairs or replacement of components and charge its then
current price, which buyer agrees to pay.
Spectracom shall not have any warranty obligations if the
procedure for warranty claims is not followed. Users must
notify Spectracom of the claim with full information as to the
claimed defect. Spectracom products shall not be returned
unless a return authorization number is issued by Spectracom.
Spectracom products must be returned with the description of
the claimed defect and identification of the individual to be
contacted if additional information is needed. Spectracom
products must be returned properly packed with transportation
charges prepaid.
Shipping expense: Expenses incurred for shipping
Spectracom products to and from Spectracom (including
international customs fees) shall be paid for by the customer,
with the following exception. For customers located within the
United States, any product repaired by Spectracom under a
“warranty repair” will be shipped back to the customer at
Spectracom’s expense unless special/faster delivery is
requested by customer.
Spectracom highly recommends that prior to returning
equipment for service work, our technical support department
be contacted to provide trouble shooting assistance while the
equipment is still installed. If equipment is returned without first
contacting the support department and “no problems are
found” during the repair work, an evaluation fee may be
charged.
EXCEPT FOR THE LIMITED WARRANTY STATED ABOVE,
SPECTRACOM DISCLAIMS ALL WARRANTIES OF ANY
KIND WITH REGARD TO SPECTRACOM PRODUCTS OR
OTHER MATERIALS PROVIDED BY SPECTRACOM,
INCLUDING WITHOUT LIMITATION ANY IMPLIED
WARRANTY OR MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE.
Spectracom shall have no liability or responsibility to the
original customer or any other party with respect to any liability,
loss, or damage caused directly or indirectly by any
Spectracom product, material, or software sold or provided by
Spectracom, replacement parts or units, or services provided,
including but not limited to any interruption of service, excess
charges resulting from malfunctions of hardware or software,
loss of business or anticipatory profits resulting from the use or
operation of the Spectracom product or software, whatsoever
or howsoever caused. In no event shall Spectracom be liable
for any direct, indirect, special or consequential damages
whether the claims are grounded in contract, tort (including
negligence), or strict liability.
EXTENDED WARRANTY COVERAGE
Extended warranties can be purchased for additional periods
beyond the standard five-year warranty for those products
covered under five-year warranty. Contact Spectracom no later
than the last year of the standard five-year warranty for
www.spectracomcorp.com
www.spectracom.fr

extended coverage.

Spectracom Corporation 8194B, 8195B, 8197B

Spectracom Corporation EPSILON CLOCK MODEL EC22S
EPSILON CLOCK User’s Manual iii
able of Contents
able of Contentsable of Contents
able of Contents
1 INTRODUCTION ............................................................................................... 1-1
1.1 Safety Precautions 1-1
1.2 Safety during Adjustments, Maintenance, and Repair 1-1
1.3 Inventory 1-2
1. Inspection 1-2
1.5 General Description 1-2
1.6 Integrated Remote Control Interface 1-3
1.7 Front and Rear Panels 1-
1.7.1 EC22S Front Panel LEDs 1-5
1.7.2 EC22S Back Panel Connectors 1-6
1.8 Dimensions and Weight 1-7
1.9 Operating Environment 1-7
1.10 Power Supply 1-7
1.10.1 DC Power Supply nput 1-7
1.10.2 AC Power Supply nput 1-7
1.10.3 Redundancy 1-7
1.11 Terminology 1-8
2 TECHNICAL FEATURES................................................................................... 2-1
2.1 Timing Reference Generation and Characteristics 2-1
2.1.1 Clock Generation 2-1
2.1.2 GPS Reception 2-1
2.1.3 1PPS external synchronization nput 2-1
2.1.4 Phase Lock-in at Power-up 2-2
2.1.5 10MHz output 2-2
2.1.6 1PPS Output 2-2
2.2 Auxilliary Connector Signals 2-3
2.2.1 Alarm Connector 2-3
2.2.2 RS232 2-3
2.3 Network Connectivity 2-
2.3.1 Ethernet nterface 2-4
2.3.2 P Address Assignment 2-4
2.3.3 P Address Exclusion 2-4

EPSILON CLOCK MODEL EC22S Spectracom Corporation
EPSILON CLOCK User’s Manualiv
2.3.4 Protocols 2-4
2. Control PC for Web Interface 2-
2.5 EMC 2-
3 PUTTING THE EC22S INTO OPERATION ....................................................... 3-1
3.1 Left and Right Clock Modules 3-1
3.2 Powering Up 3-1
3.3 Network Connection 3-2
3. Configure the EPSILON CLOCK Model EC22S 3-2
4 OPERATION...................................................................................................... 4-1
.1 General Information -1
4.1.1 Control of operating functions 4-1
4.1.2 Network Configuration 4-1
4.1.3 Redundancy 4-2
4.1.4 Clock Generation on Clock Modules 4-2
4.1.5 Clock Switchover 4-3
4.1.6 Distribution Monitoring 4-3
4.1.7 GPS Reception 4-3
4.1.8 Equipment Start-up 4-4
4.1.9 Clock Module Hot Plugging 4-4
.2 Front Panel Control -
4.2.1 Navigation with Keypad and LCD Display 4-4
4.2.2 Screens 4-5
.3 Alarm-Time Connector -8
5 WEB INTERFACE ............................................................................................. 5-1
5.1 General Description 5-1
5.2 Web Pages 5-1
5.2.1 Welcome Page 5-1
5.2.2 Upper task bar and page header 5-2
5.2.3 Clock Status page 5-3
5.2.4 Admin Password page 5-9
5.2.5 Network Setup page 5-9
5.2.6 SNMP Setup page 5-11
5.2.7 Time & Reference Setup page 5-14
5.2.8 GPS Setup page 5-18
5.2.9 Power Setup page 5-19
5.2.10 Events logging 5-20
5.2.11 Versions 5-21

Spectracom Corporation EPSILON CLOCK MODEL EC22S
EPSILON CLOCK User’s Manual v
5.2.12 Software Upgrade 5-22
5.2.13 Reboot 5-23
6 SNMP CONTROL .............................................................................................. 6-1
6.1 MIB Content 6-1
6.2 SNMP TRAPS 6-2
7 MAINTENANCE................................................................................................. 7-1
7.1 Periodic Verification and Calibration 7-1
7.2 Updating the Software Version 7-1
7.3 Spare Parts 7-1
7. Troubleshooting 7-1
7.4.1 Searching for Alarm Origin 7-1
7.4.2 What Can Be Done 7-3
8 APPENDIX......................................................................................................... 8-1
8.1 Pin-Out of EC22S connectors 8-1
8.1.1 RJ45 - Ethernet 8-1
8.1.2 DC Power Supply –48VDC 8-1
8.1.3 BNC – Outputs Freq (1 to 8) 8-1
8.1.4 BNC – External Ref nput 8-2
8.1.5 TNC - GPS Antenna 8-2
8.1.6 Alarms 8-2
8.2 GPS Antenna Installation 8-2
8.2.1 GPS Antenna Location 8-2
8.2.2 Gain calculation 8-3

EPSILON CLOCK MODEL EC22S Spectracom Corporation
EPSILON CLOCK User’s Manualvi

Spectracom Corporation EPSILON CLOCK MODEL EC22S
EPSILON CLOCK User’s Manual 1-1
1
11
1 Introduction
IntroductionIntroduction
Introduction
This manual contains information and warnings that must be understood and followed by the
customer to ensure reliable operation and long service life. It is applicable to EPSILON CLOCK
Model EC22S with software versions 1.04b or higher.
1.1
1.11.1
1.1 Safety Precautions
Safety PrecautionsSafety Precautions
Safety Precautions
•Before switching on the unit, ensure that it is compatible with the local mains supply.
(Refer to Setting the EC22S Into Operation).
•The plug must be inserted into a socket with earth connection. The safety connection
must not be broken by using an extension cord without earth conductor.
•Before switching on the unit, if the unit is connected to measurement or control circuits,
protective earth terminal(s) shall be connected to a protective conductor.
•If measurement or control circuits are without earth-ground protection terminal(s), the
mains plug shall be inserted before connections are made to measurement or control
circuits.
WARNING: If the protective conductor's path to ground is broken or
defeated, the danger of electrical shock to the operator
may be present. Never break the connection on purpose.
Before disconnecting the unit from the main power
supply, always switch it off. Failure to do may cause
damage that voids your Spectracom warranty.
1.2
1.21.2
1.2 Safety during Adjustments, Maintenance, and Repair
Safety during Adjustments, Maintenance, and RepairSafety during Adjustments, Maintenance, and Repair
Safety during Adjustments, Maintenance, and Repair
When the unit is connected to the power supply, it may be dangerous to touch the terminals and
parts that may be exposed when opening covers or removing components (except for plug-in
components).
The unit must be disconnected from all power sources before carrying out any adjustments,
replacements, maintenance, or repair.
When it is unavoidable to open the unit for maintenance and repair, such operations should be
carried out only by qualified personnel who are properly informed of the hazards involved.
Only fuses with a suitable rating and of the specified type are to be used for replacement
purposes. It is prohibited to use fuses that have been tampered with, or shorted fuse-holders.
For special hot plugging removal, please follow the instructions Maintenance.

EPSILON CLOCK MODEL EC22S Spectracom Corporation
EPSILON CLOCK User’s Manual1-2
WHENEVER IT IS LIKELY THAT PROTECTION HAS BEEN IMPAIRED, THE APPARATUS
MUST BE SWITCHED OFF, DISCONNECTED, AND SECURED AGAINST ANY
UNINTENDED OPERATION.
1.3
1.31.3
1.3 Inventory
InventoryInventory
Inventory
Before installing your Spectracom product, please verify that all material ordered has been
received. If there is a discrepancy, please contact Spectracom Customer Service. Customer
service is available by telephone at +33 (0) 1.64.53.39.80 (France), +33 (0) 1.64.53.94.29
(France direct), or +1.585.321.5800 (United States).
CAUTION: Electronic equipment is sensitive to Electrostatic
Discharge (ESD). Observe all applicable ESD
precautions and safeguards when handling the
Spectracom equipment.
NOTE: If equipment is returned to Spectracom, it must be shipped in its original packing
material. Save all packaging material for this purpose.
The basic shipment includes the following items:
•EPSILON EC22S Base Unit with two Clock modules
•Two 48 VDC Bulgin power plugs
•Two AC leads
•User’s Manual
1.4
1.41.4
1.4 Inspection
InspectionInspection
Inspection
Unpack the equipment and inspect it for damage. If any equipment has been damaged in
transit, please contact Spectracom Customer Service. Customer service is available by
telephone at +33 (0) 1.64.53.39.80 (France), +33 (0) 1.64.53.94.29 (France direct), or
+1.585.321.5800 (United States).
1.5
1.51.5
1.5 General Description
General DescriptionGeneral Description
General Description
The EPSILON CLOCK 22S is a fully redundant GPS Clock, providing the best cost-effective
solution for reliable, and 24-hour-a-day, uninterrupted applications. The EC22S is particularly
well-suited for broadcast operators requiring high quality, reliability, and availability.
The Spectracom ECC22S is well dedicated to digital broadcast applications using SFN (Single
Frequency Network) mode. The EC22S gives the high reliability required at any step of the
network, from SFN adapters to high- and medium-power transmitters and gap fillers.

Spectracom Corporation EPSILON CLOCK MODEL EC22S
EPSILON CLOCK User’s Manual 1-3
The EPSILON CLOCK 22S provides accurate time and frequency synchronization.
Key parameters are:
•Total redundancy — dual High performance OCXO disciplined by GPS through Epsiltime©
smart predictive slaving algorithm
•Smart switching with glitch-less Clock switchover and very low phase jump, in case of Clock
failure
•High performance holdover stability (2.10
-10
/day)
•AC and 48VDC power supply redundancy
•Hot-plugging servicing
•Up to 8 x 1 PPS outputs
•Up to 8 x 10 MHz outputs
•1 PPS and 10 MHz signal are phased locked, which helps prevent phase jump and wander
between time and frequency signals
•Remote management by SNMP/HTTP, through Ethernet port
The quality of the internally generated reference Clock is related to the OCXO performance and
the high performance tracking algorithm:
Accuracy in GPS slaving Holdover stability Holdover short-term stability
OCXO < ± 2x10
-12
(24h) < ± 2x10
-10
/day < ±3x10
-11
/100 sec
Table 1 - 1. Frequency accuracy and stability.
1.6
1.61.6
1.6 Integrated Remote Control Interface
Integrated Remote Control InterfaceIntegrated Remote Control Interface
Integrated Remote Control Interface
The EC22S contains an Ethernet IP interface so that it can be fully controlled from a remote
location.
The EC22S includes its own HTTP web server so that a simple navigator is sufficient to
configure and retrieve status from the equipment. Application and system software release is
also possible through this interface.
Moreover, network supervision can be achieved with SNMP protocol, especially traps sent to a
programmable IP address.

EPSILON CLOCK MODEL EC22S Spectracom Corporation
EPSILON CLOCK User’s Manual1-4
1.7
1.71.7
1.7 Front and Rear Panels
Front and Rear PanelsFront and Rear Panels
Front and Rear Panels
Figure 1 - 1.EC22S front panel and back panel.

Spectracom Corporation EPSILON CLOCK MODEL EC22S
EPSILON CLOCK User’s Manual 1-5
Functions of the EC22S include:
•Clock generation (including GPS reception, internal oscillator, power converters) on the two
Clock modules
•Clock switching for right/left selection of distributed Clock
•Clock distribution and monitoring
•Management
1.7.1 EC22S Front Panel LEDs
1.7.1.1 Clock Module LEDs
SEL
Green Indicates the current selected module providing distributed frequency. Green on the
Master module, off on the Slave module.
GPS
Green/
Red
Indicates the current status of the GPS reception. Green for reception OK, red for
alarm.
LOCKED/OK
Green/
Red
Indicates the current status of the tracking algorithm. Red during warm-up, tracking
start, and green after locking to a reference input. Orange indicates non-urgent
alarm
1.7.1.2 Front Panel LEDs
ETH
Green Indicator of Ethernet connection. Green indicates good physical connection with
network. LED is off if Eternet network is not connected.
EXTREF
Green/
Red
Alarm indicator on External 1PPS input. Red if input enabled and in alarm, green if
input enabled and OK.
OUT FRQ
Green/
Red
Indicates the current status of the 4 (or 8) x distributed frequency outputs. Red if
one or more channels are not present. Should always be green.
OUT 1PPS
Green/
Red
Indicates the current status of the 4 (or 8) x distributed 1PPS. Red if one or more
channels are not present. Should always be green.

EPSILON CLOCK MODEL EC22S Spectracom Corporation
EPSILON CLOCK User’s Manual1-6
On normal operation, all LEDs should be green. Only available reference input sources
should be enabled. Only available power alarms should be enabled.
1.7.2 EC22S Back Panel Connectors
AC POWER (90 to 230 VAC)
Schaffner AC power entry with integrated fuse
DC POWER (-48 VDC)
Bulgin
circular
Nominal -48 VDC power supply input. One Input and DC/DC converter per Clock
module provides redundancy
Freq (4 + option 4)
50 Ω
BNC Distributed sinus frequency outputs
1PPS (4 + option 4)
50 Ω
BNC Distributed One Pulse Per Second outputs
Ethernet 10/100 BaseT
RJ45 Network connectivity.
GPS Antenna
50 Ω
TNC Antenna inputs for GPS receiver and remote active antenna 5VDC supply
EXTERNAL PPS
50 Ω
BNC External 1PPS reference input
ALARMS
SubD 9 Dry contacts
GROUND
Casing grounding.

Spectracom Corporation EPSILON CLOCK MODEL EC22S
EPSILON CLOCK User’s Manual 1-7
1.8
1.81.8
1.8 Dimensions
DimensionsDimensions
Dimensions and Weight
and Weight and Weight
and Weight
Width: 19" (441 mm), without bracket
Height: 2 U (88 mm).
Depth: 400 mm + 40 mm (front panel handles).
Weight: <6.5 kg.
Compatiblity: 19” rack
1.9
1.91.9
1.9 Operating Environment
Operating EnvironmentOperating Environment
Operating Environment
- Operating temperature: 0 to 50°C
- Storage temperature: -40 to 85°C
- Relative humidity: 95 % non-condensing
- Electromagnetic compatibility: in accordance with EN30386/EN55022/EN60950
1.10
1.101.10
1.10 Power
PowerPower
Power Supply
Supply Supply
Supply
1.10.1 DC Power Supply Input
- Nominal DC input voltage: -48 Volts
- Normal variation: -40 to - 57 Volts
- Transitory variation: -37 to - 72 Volts
- Nominal DC input voltage conditions: -48 Volts DC
- Maximum Total Power consumption: < 55 W
- Two independent input, two connectors
- Protection against polarity reversal
- -48V and 0V DC input wires are not ground referenced
- Every module protected by a PolySwitch fuse (automatically rearmed)
- Detection of power input presence on each connector, information available on LCD display
or with remote control software, threshold level of detection between -35 and -40 Volts
1.10.2 AC Power Supply Input
- Nominal AC input voltage: 90 to 264 Volts AC / 48 to 63 Hz
- Two independent power input, two connectors/switches
- On each switch: 2 fuses: D1TD 2A 5x20
- Detection of power input presence on each AC/DC converter, information available with
remote control software
1.10.3 Redundancy
Power supply redundancy exists at two levels: between AC and DC and between Left and Right
module converters.
If the AC Input power supply is present, DC input is internally disconnected. If AC input fails, DC
input switches over to supply the equipment.

EPSILON CLOCK MODEL EC22S Spectracom Corporation
EPSILON CLOCK User’s Manual1-8
There is one AC converter and one DC converter on each Clock module. The power supply for
distribution and management is a combination of sources from both modules.
1.11
1.111.11
1.11 erminology
erminologyerminology
erminology
GPS Global Positioning System
OCXO Oven Controlled XTAL (Crystal) Oscillator
Rb Rubidium oscillator
S/A Selective Availability
TRAIM Time Receiver Autonomous Integrity Monitoring
UTC Universal Time Coordinated
1PPS One Pulse Per Second
1 PPS driver Pulse signal obtained through division of the frequency driver
Holdover If the reference input signal is lost, the EPSILON CLOCK® maintains the
generation of information and of time and frequency signals.
Reliability Concerns the positioning mode of the antenna. In automatic mode, the
EPSILON CLOCK® calculates the position of the antenna and, after
testing the result, imposes the reliable position on the internal GPS
receiver. The receiver therefore functions in GPS 0D reception mode. The
EPSILON CLOCK® is synchronized by following at least one satellite.
Frequency driver Frequency signal generated by the built-in oscillator.
Reference input Time and frequency source used by the EPSILON CLOCK®.
IERS International Earth Rotation Service.

Spectracom Corporation EPSILON CLOCK MODEL EC22S
EPSILON CLOCK User’s Manual 2-1
2
22
2 echnical Features
echnical Featuresechnical Features
echnical Features
2.1
2.12.1
2.1 iming Reference Generation and Characteristics
iming Reference Generation and Characteristicsiming Reference Generation and Characteristics
iming Reference Generation and Characteristics
The following characteristics are minimum values. Enhanced performance options are
available.
2.1.1 Clock Generation
2.1.1.1 Clock Type
- Type of local oscillator: OCXO High Perfromance
- Clock generated from GPS reference
- Loop filter type: Kalman predictive algorithm
2.1.1.2 Holdover Mode
- According to EN 300 462-4-1 (9.2)
- Stability < ± 2x10
-10
/day.
2.1.1.3 Short Term Stability (Allan Variance)
- 1s: 1x10
-11
- 10s: 3x10
-11
- 100s: 3x10
-11
2.1.1.4 Temperature Stability
Peak to peak, from 0 to 60°C: 1x10
-9
2.1.2 GPS Reception
- Connector: Antenna female 50 ΩTNC
- 2 x L1 GPS C/A code
- Power supply to active antenna: 5V/80 mA max
- Fold Back protection: The power supply is cut in the event of a short-
circuit in the antenna input
2.1.3 1PPS external synchronization Input
- TTL level
- Input impedance: 50Ω
- 50ΩBNC connector

EPSILON CLOCK MODEL EC22S Spectracom Corporation
EPSILON CLOCK User’s Manual2-2
2.1.4 Phase Lock-in at Power-up
2.1.4.1 Warming-up
-Warm-up time for the local oscillator before tracking search: 10 minutes
-A subsequent fast tracking search brings the oscillator frequency close to the reference
input signal frequency
2.1.4.2 Lock-in Time with GPS signal
- Output wander compatible with EN 300 462-4-1 (4.1) fig. 1 in: 600 s max after warming-
up
- Optimum stabilization after 2 hours
- Total locking time after power-up: < 30 minutes if not a first time power-up
2.1.5 10MHz output
- Number of outputs: 8.
- Port type: 50ΩBNC coaxial.
- Level: 12+/-2dBm, with a 50Ωload.
- Sinewave signal, -35dBc harmonic distortion
2.1.5.1 Phase Noise
Typical, static conditions:
10Hz -120dBc/Hz
100Hz -130dBc/Hz
1kHz -140dBc/Hz
10kHz -145dBc/Hz
100kHz -145dBc/Hz
2.1.6 1PPS Output
- Number of outputs: 8
- One female 50ΩBNC coaxial connector per output
- Accuracy to UTC, GPS locked: +/- 25ns (1σ)
- Accuracy to UTC instantaneous (phase locked): +/- 35ns max (peak to peak)
- Phase jump on switching (phase locked): +/- 70ns max (peak to peak)
Holdover (constant temperature, 24 hours GPS locked)
after 4 hours 0.8 µs
after 1 day 12 µs
- Port type: 50Ωcoaxial.
- Level: TTL/5V, with a 50Ωload.