CATV Linx 2809 Guide

825 Park Street Christiansburg, VA 24073 • TEL [phone] • FAX [phone] • USA [phone] • [e-mail] • www.forceinc.com
Model 2809
LDS CATV Receiver
IOM2809
Revision 2.0, March 2004
Instructions for Installation and Use
Read this manual before installing or using this product.
Observe all safety warnings and cautions.
Copyright © 2004 by Force, Incorporated. All rights reserved. Force, Incorporated reserves the right to make changes
to the product described in this document in the interest of document improvement.

Model 2809 CATVLinx® LDS CATV Receiver
Revision 2.0 ii
About this Manual
This manual explains how to configure and install the Model 2809 LDS CATV
receiver. It is intended for engineers and technicians who will install the 2809R
receivers with companion transmitter, Model 2806 (see IOM2806). While this
guide provides basic information on how to configure and install the units, it
assumes that you as the user are familiar with:
• the installation and manipulation of electronic and fiber optic equipment
• the installation and manipulation of CATV video/audio equipment
This manual is divided into the following sections:
•Section 1, page 1: Describes the LDS CATV receiver, lists technical specifica-
tions, performance graphs, system applications, and ordering information.
•Section 2, page 7: Describes the installation of the LDS CATV receiver, connec-
tions, and safety precautions.
•Section 3, page 11: Describes the operation of the LDS CATV link, trouble-
shooting, and user maintenance.
A quick-reference index completes the user manual.
Related Documentation
• IOM2806: User Manual for Model 2806 LDS Transmitter
• AN123: North American Television Frequencies
• AN128: Care and Feeding of Analog CATV Fiber Optic Links
• AN141: System Solutions for CATV HFC Networks
•Fiber Optic Reference Guide, 3rd Edition. by David R. Goff (Focal Press 2002):
General theory and operation of fiber optic units.
• Web Site: Our web site, http://www.forceinc.com may be used to download
the latest versions of this manual.
Preface

Model 2809 CATVLinx® LDS CATV Receiver Preface
Revision 2.0 iii
Technical Support
If you encounter any kind of problem after reading this manual, contact your local
distributor or a Force, Inc. Applications Engineer. To reach technical support:
Warranty
Force, Incorporated standard products are warranted to be free from defects in
materials and workmanship, meeting or exceeding factory specified performance
standards for a period of three (3) years from date of purchase.
Force Obligations
Force will, at its discretion and expense, repair any defect in materials or work-
manship or replace the product with a new product. Force will, upon receipt of
the return, evaluate the product and communicate to the customer the nature of
the problem, and determine if the claim falls under warranty coverage.
If during the warranty period, Force is unable to repair the product to the original
warranted state within a reasonable time, or if subcomponents of the unit have
been obsoleted or discontinued, then Force has the option to provide an equiva-
lent unit.
Exclusions
This warranty does not extend to any product that has been damaged due to acts
of God, accident, misuse, abuse, neglect, improper system design or application,
improper installation, improper operation or maintenance, or connection to an
improper voltage supply.
The Force warranty does not cover fuses, batteries, and lamps. Modifications or
alterations of Force products (including but not limited to installation of non-Force
equipment or computer programs), except as authorized by Force, will void this
warranty. Removal or breaking of the seals on the product will also void the war-
ranty. In addition, cost of repair by unauthorized persons within the warranty
period of the product will not be covered by Force, Incorporated. Such repairs
will void the warranty.
On the Web: http://www.forceinc.com
By Phone (Monday through Friday 8:00 am
to 5:00 pm EST):
USA [phone]
TEL [phone]
By Fax: [phone]
By Email: [email protected]

Preface Model 2809 CATVLinx® LDS CATV Receiver
iv Revision 2.0
Force, Incorporated makes no other representation or warranty of any other kind,
express or implied, with respect to the goods, whether as to merchantability, fit-
ness for a particular purpose, or any other matter. Force, Incorporated’s liability
shall not include liability for any special, indirect or consequential damages, or for
any damages arising from or attributable to loss of use, loss of data, loss of good-
will, or loss of anticipated or actual revenue or profit, or failure to realize expected
savings, even if Force, Incorporated has been advised of the possibility of such
damages. This warranty constitutes Force, Incorporated’s entire liability and the
customer’s sole remedy for defects in material and workmanship.

Model 2809 CATVLinx® LDS CATV Receiver
Revision 2.0 v
Preface................................................................................................................. ii
Section 1 Product Technical Bulletin..................................................................... 1
1.1 Product Overview................................................................................................. 1
1.2 FCC Notice ........................................................................................................... 1
1.3 Optical, Video, Electrical Characteristics ................................................................ 1
1.4 Environmental and Physical Characteristics ........................................................... 2
1.5 Specification Notes ............................................................................................... 2
Figure 1.1 In-Band Frequency Response .......................................................... 2
Figure 1.2 Expanded Frequency Response ....................................................... 3
Figure 1.3 CNR vs. Receiver Optical Input at 77 Channels .............................. 3
Figure 1.4 RF Output Level Behavior of 2809R................................................4
1.6 Applications.......................................................................................................... 5
Figure 1.5 Private Network Configuration ....................................................... 5
1.7 Ordering Information............................................................................................ 5
Section 2 Installation Instructions ................................................................ 7
2.1 General Installation Requirements......................................................................... 7
2.2 Items Provided...................................................................................................... 7
2.3 Items Required ..................................................................................................... 7
2.4 Inspection............................................................................................................. 8
2.5 Module Placement................................................................................................8
2.6 Unit Outline Drawing ........................................................................................... 8
Figure 2.1 Model 2809 CATVLinx®LDS CATV Receiver..................................... 8
2.7 Connections ......................................................................................................... 9
2.8 Safety Precautions ................................................................................................ 9
2.8.1 Laser Safety Procedures ....................................................................... 9
2.9 Shipping and Handling Precautions..................................................................... 10
2.10 Storing the Unit ................................................................................................ 10
Contents

Contents Model 2809 CATVLinx® LDS CATV Receiver
vi Revision 2.0
Section 3 Operating Instructions ........................................................................ 11
3.1 Theory of Operation ...........................................................................................11
Figure 3.1 Model 2809 Block Diagram ..........................................................11
3.2 Power-up and Operation ....................................................................................11
3.3 Measuring RF Input Levels at the Transmitter .....................................................12
3.4 Performance Verification..................................................................................... 12
3.5 Cleaning ............................................................................................................. 13
3.5.1 Connector Cleaning...........................................................................13
3.5.2 Connector Handling...........................................................................14
3.6 Troubleshooting..................................................................................................14
3.7 Repair Service .....................................................................................................14
Index ................................................................................................................. 15

Model 2809 CATVLinx® LDS CATV Receiver
Revision 2.0 1
1.1 Product Overview
The Force, Incorporated CATVLinx®Model 2809 Limited Distance Solution
(LDS) CATV Receiver, working with the Model 2806 LDS transmitter, provides
a low-cost system for transporting 77 channels of VSB/AM modulated signals over
a single-mode optical fiber. The LDS link provides excellent performance up to 10
km with full channel loading, high sensitivity, and 40-550 MHz of usable band-
width. With a wide optical input range of -8.0 dBm to +4.5 dBm and an RF output
of +18 dBmV at 0 dBm optical input, the Model 2809 allows high quality signal
transport for intra-facility limited distance applications, such as corporate CATV
delivery and FTTC where cost, small size, and performance are major consider-
ations. This low-cost system allows CATV providers with the ability to provide a
reliable limited distance fiber optic video distribution system.
1.2 FCC Notice
The Model 2809 has been tested and found to comply with the limits for a Class A
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference when the equipment
is operated in a commercial environment. This equipment generates, uses, and
can radiate radio frequency energy and, if not installed and used in accordance
with the instructions in this manual, may cause harmful interference, in which
case the user must correct the interference at the user’s own expense. Compliance
with applicable regulations depends on the use of shielded I/O cables. The user is
responsible for procuring the appropriate cables.
1.3 Optical, Video, Electrical Characteristics: @ 25 °C, SM Fiber (Note 9)
Min. Typ. Max. Units Notes
See Section 1.5
Operating Wavelength 1290 1310 1330 nm
Operating Wavelength 1490 1550 1610 nm
Optical Input Power -8.0 +4.5 dBm
Channel Loading 77 Channels
Bandwidth 40 550 MHz
Required Fiber Bandwidth 2,000 MHz
Output Impedance 75 Ohms
RF Output Level +18 dBmV 1, 2
Section 1 Product
Technical Bulletin

Product Technical Bulletin Model 2809 CATVLinx® LDS CATV Receiver
2Revision 2.0
1.4 Environmental and Physical Characteristics
1.5 Specification Notes
1) The 2809 receiver does not include an adjustable RF output level. The unit is
designed to give approximately an RF output of +18 dBmV per channel at an
optical input of 0 dBm. The RF level will change by 2 dB for every 1 dB
change in optical input. At an optical input of -8.0 dBm, the RF level will be
about +2 dBmV per channel. At an optical input of +4.5 dBm, the RF level
will be approximately +27 dBmV per channel.
2) Figure 1.1 shows the typical frequency response of a 2806T/2809R link over
the specified frequency range. The gain flatness is ±1.5 dB over this range.
The flatness is typically less than ±0.1 dB over a standard 6 MHz channel
bandwidth. See Application Note AN123 for additional information on North
American Television Frequencies.
Figure 1.1 In-Band Frequency Response
Output Return Loss 16 dB
Composite Second Order (CSO) -63 dBc
Composite Triple Beat (CTB) -66 dBc
Carrier-to-Noise Ratio (CNR) See Figure 1.3, page 3. 3
Backreflection Tolerance -50 dB 5
Power Supply Voltage +8 +10 VDC 6
Power Dissipation 2 Watts
Min. Typ. Max. Units Notes
See Section 1.5.
Operating Temperature Range 0 +50 °C 7
Storage Temperature Range -20 +70 °C
Humidity 5 95 % 8
Weight 6.6 oz.
187 g
Physical Dimensions 3.75 x 2.95 x 1.12 in.
95 x 75 x 29 mm
Min. Typ. Max. Units Notes
See Section 1.5
0 100 200 300 400 500 600 700 800 900 1000
-30
-25
-20
-15
-10
-5
0
5
Frequency (MHz)
Response (dB)

Model 2809 CATVLinx® LDS CATV Receiver Product Technical Bulletin
Revision 2.0 3
Figure 1.2 shows an expanded view of the frequency response of a typical
2806T/2809R link.
Figure 1.2 Expanded Frequency Response
3) Figure 1.3 show the CNR versus received optical input power and number of
channels. The horizontal axis is the amount of optical light that reaches the
receiver. (It is not the loss between the transmitter and receiver.) The vertical
axis shows the CNR.
Figure 1.3 CNR vs. Receiver Optical Input at 77 Channels (2806T with 2809R)
The link CNR is usually specified for a received optical power of -3 dBm or
more. Thus, a 2806T-SCSP optical transmitter, with an optical output of +4.5
dBm, will provide optimal performance with up to 7.5 dB of optical loss at full
channel loading. If lower channel loading is used, then the link can operate at
higher optical losses and still provide exceptional CNR.
Typical transmitter output is +4.5 dBm, so a received optical power of -3.5
dBm corresponds to an optical loss of 8 dB. Five curves are plotted; the top
curve is the typical result when only 5 channels are transmitted through the
link. It can be seen that very high CNR results and in fact the output is quite
usable with receiver optical inputs as low as -12 dBm, corresponding to 16 dB
of optical loss! As the channel loading gets higher, the maximum achievable
CNR drops.
50 100 150 200 250 300 350 400 450 500 550
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
Receiver Optical Input (dBm)
Carrier-to-Noise Ratio (dB)
5 Ch.
10 Ch.
24 Ch.
40 Ch.
77 Ch.
36
38
40
42
44
46
48
50
52
54
56
58
60
62
64
-12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 01234

Product Technical Bulletin Model 2809 CATVLinx® LDS CATV Receiver
4Revision 2.0
4) Figure 1.4 shows the RF output behavior of the 2809 receiver. The blue line
shows the nominal Rf output level versus optical input. Over the optical input
range from -8 dBm to +4.5 dBm, the RF output level varies by 2 dB for every
1 dB drop in optical input power. Operating below -8 dBm optical input will
cause the CNR to degrade rapidly for channel loads of 77 or more.
Figure 1.4 RF Output Level Behavior of 2809R
In Figure 1.4 the central green area is the region that should be used for new
designs. So while the receiver is rated to optical input powers as low as -8
dBm, it is recommended that -6 dBm be the minimum for a newly installed
system. That leaves 2 dB of margin for the optical power to drop and still pro-
vide good operation. The yellow region is the safety band. The unit is rated to
operate in this region; however, the margin will probably be inadequate for a
newly installed design. The red regions are outside the recommended operat-
ing parameters of the 2809R and must be avoided to ensure reliable opera-
tion.
5) This product must be used only with APC type optical connectors or
fusion spliced connections. There is some folklore which suggests that the
only critical backreflection is the one closest to the transmitter. Our experience
does not support that view. We find that all backreflections matter, regardless
of their distance from the transmitter.
6) Force, Inc. recommends using the Model PS095 wall-mount power supply
(see TB043) with the Model 2809 receiver.
7) Most parameters are relatively unaffected by varying temperature. A moving
air environment is recommended at ambient temperatures above +35°C.
8) Humidity is RH non-condensing.
9) The CATVLinx®LDS CATV receiver is optimized for single-mode operation only.
Use on multimode fiber is not recommended, even for short distances,
because of the large amount of modal noise that could result.
-10
-2
0
2
4
6
8
10
RF Output Level (dBmV/Channel)
12
14
16
18
20
22
24
26
28
30
-8
Optical Input (dBm)
-6 -4 -2 0246