YDI Wireless LUC2400E Wireless LAN User Manual NM5 LUC2400E UserManRev2 8

YDI Wireless Wireless LAN NM5 LUC2400E UserManRev2 8

users manual

Model AMP2440 Pole Mounted Bi-Directional Power Amplifiers for 2.4 GHz Installation and Operation Manual Version 2.8 www.ydi.com May 2002 8000 Lee Highway 201 North Fourth St. Falls Church, VA 22042 Suite 100, San Jose, CA 95112 Tel: (703) 205-0600 Fax: (703) 205-0610 Tel: (408) 291-0998 Fax: (408) 291-0987 Sales: 1-888-297-9090 Sales: 1-800-664-7060
i TABLE OF CONTENTS 1.0 DESCRIPTION................................................................................................. 1 2.0 AMPLIFIER FEATURES................................................................................ 1 3.0 DEVICE SPECIFICATIONS.......................................................................... 2 4.0 AMPLIFIER KIT ............................................................................................... 4 5.0 INSTALLATION AND CABLING INSTRUCTIONS.................................. 5 6.0 AMPLIFIER CONNECTIONS AND INDICATORS .................................. 6 7.0 DC POWER INJECTOR OPERATION....................................................... 7 8.0 DC POWER INJECTOR CONNECTIONS AND INDICATORS ........... 7 9.0 POWER SUPPLY............................................................................................ 7 10.0 OPERATION ..................................................................................................... 8 11.0 TYPICAL AMPLIFIER INSTALLATION DETAILS.................................... 8 APPENDIX A ................................................................................................................. 9 APPENDIX B ............................................................................................................... 11 APPENDIX C ............................................................................................................... 15 © 2002 Young Design, Inc. All Rights Reserved. No part or parts of this document may be reproduced, translated, stored in any electronic retrieval system or transmitted in any form or by any means electronic, mechanical, photocopied, recorded or otherwise without the prior written permission of Young Design, Inc.
ii PROFESSIONAL INSTALLATION REQUIRED The Model AMP2440 Amplifier and antennas used must be professionally installed by experienced antenna installation professionals who are familiar with radio frequency (RF) issues such as gains and losses, as well as local building and safety codes. Failure to do so will void the product warranty and may expose the end user to excessive RF hazards. Regulations regarding maximum antenna gains, amplifier power gain and maximum permissible exposure vary from country to country. It is the responsibility of the end user to operate within the limits of these regulations and to ensure that the professional installers adhere to the antenna installation instructions contained in this manual and comply with RF exposure regulations for transmitter operating conditions. All antennas are intended to be installed outdoors. FCC NOTICE This device complies with FCC radiation exposure limits set forth for an uncontrolled environment when installed as directed. The antenna/transmitter device must be fixed-mounted on outdoor permanent structures with a separation distance of at least 2 meters between the antenna and all persons during normal operation. This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference and (2) This device must accept any interference received including interference that may cause undesired operation.
iii LIMITED WARRANTY Young Design, Inc. (YDI) warrants that your device is free of defects in material and workmanship for a period of one year after initial purchase. YDI will, in this period of time, repair or replace, any YDI product returned to the factory, freight prepaid. The YDI warranty covers repairs or replacement (at YDI’s option) of the product only. YDI is not responsible for the cost of removal, reinstallation or shipping to the place of repair. YDI does not extend or modify its warranty period as a result of repair or replacement. YDI reserves the right to void a warranty and/or make reasonable charges for repair of a unit if the warranty seal is broken or the unit displays evidence of misuse, abuse or tampering. YDI is not responsible for damage to any other equipment or property, or any other consequential or incidental damages of any kind, whether based on contract, negligence, or strict liability. Maximum liability shall not in any case exceed the purchase price of the unit. Warranties give you (the buyer) specific legal rights. You may also have other rights that vary from state to state. This warranty is only extended to purchases made in the United States of America or its possessions. Warranty Notice The AMP2440 warranty is null and void if any of the following occurs: 1. The amplifier is opened. 2. The antenna connections are not properly waterproofed. 3. The amplifier is operated with no antenna attached. 4. Improper connectors are used. 5. The amplifier is mounted outdoors with the connectors facing any direction except downward.
1Installation and Operation Manual AMP2440 Power Amplifier 1.0 Description The AMP2440 is a bi-directional amplifier designed for extending the range of 2.4 GHz wireless radio modems, Wireless LAN cards, Access Points and wireless bridges. The units provide transmit power amplification as well as receive signal gain. The amplifier is installed right at the antenna’s feed point, providing maximum effectiveness of transmit power. This has the effect of compensating for signal loss in the transmitter cable to the antenna. Likewise, the Low Noise Amplifier (LNA) in the AMP2440 boosts the receive signal right at the antenna prior to experiencing the loss in the transmission cable to the radio. This gain completely overcomes the losses in the transmission cable between the amplifier and the radio. This results in the lowest possible system Noise Figure. In fact, use of the amp will actually increase the receiver sensitivity by a few dB! The ultimate result is the best receiver sensitivity and maximum possible range for whatever antenna is used. The amplifier box is weatherproof and can be bolted to the antenna mast or tower leg using the U-bolt included. When properly installed, the connectors face down so that gravity will drain all water away from the amplifier enclosure. This will prevent water from settling on the face of the unit. The LEDs will also be facing downward so that they can be checked for operation from the bottom of the mast or tower. DC Power to the amplifier is supplied through the transmission cable that carries the RF (Radio Frequency) signal. This DC voltage is put on the coax cable using the DC Power Injector included in the amplifier kit. Both the amplifier and the DC Injector also contain their own integral lightning protection as well as DC surge protection. No external antenna lightning protection on the coax cable is required. The DC Injector has a grounding stud to facilitate an easy connection to a good earth ground. It also has mounting flanges to facilitate permanent installation to a bulkhead or wall. If mounted to a grounded metal plate, then no extra grounding wires are needed. The amplifier box will provide maximum lightning protection when it is bolted to a grounded mast or tower. No extra ground straps need to be connected to the amplifier case. 2.0 Amplifier Features • Transmit input levels from 3mW to 100mW, (10mW for the standard amp) • 14 dB transmitter power gain (standard amp) • 16 dB receive gain • RX preamp noise figure better than 4 dB (typical) • Mast-mountable weatherproof cast aluminum case • DC power for the amp carried up through the transmission cable • Power and Transmit LEDs on both the amp and the DC power injector • Built-in lightning protection • DC surge protection • Heavy duty N-type connectors • One-year warranty • Made in the U.S.A.
2 3.0 Device Specifications General Operating Range: 2400-2483 MHz Operating Mode: Bi-directional, half-duplex. Senses RF carrier from transmitter and automatically switches from receive to transmit mode. Connectors: N-female Indicators: TX and RX LEDs on both the amplifier and the DC bias injector Lightning Protection: Direct DC ground at antenna connector. DC injector serves as lightning arrestor if properly grounded. DC Surge Protection: 600 Watt TVS at 12 VDC input from transmission cable Transmitter Amplifier Transmit Gain: 14 dB nominal for standard amp (Other versions may have different gains) Frequency Response: Transmit Output Power: Duty Cycle: +/-1 dB over operating range 250 mW nominal Up to 640 mW for FHSS radios Up to 400 mW for DSSS radios 50% Maximum Transmit Input Power to Amp: 3mW minimum (+5 dBm), 10mW nominal (+10 dBm) 100mW (20 dBm) maximum (Special versions are available with higher input power). Receiver Low Noise Amplifier (LNA) Receive Gain: 16 dB nominal Frequency Response: +/-1 dB over operating range Noise Figure: 2.8 dB typical, 3.8 dB max at room temperature. Mechanical, Power and Environmental Operating Temperature: 20°C to +60°C Power: 105-240 VAC if using the power supply provided with the amp kit or 11 - 14 VDC @ 900 ma peak, 400 ma avg. with an alternate power source Dimensions: Amplifier: 4.5” x 2.6” x 1.2” DC Power Injector: 5.4” X 2.4” X 1.3” Mounting Bracket for Amplifier: Accommodates pole/mast diameters from 3/4” to 3” Kit Weight: Approx. 1.5 lb. with U-bolts
3 3.0 Device Specifications (Continued) Model 2440 Functional Block Diagram View showing the DC Injector and the pole mounted outdoor Amplifier attached to its mounting bracket.
4 4.0 Amplifier Kit Each Amplifier Kit Includes: • Bi-directional remote mounted amplifier • DC Power Injector • 12 VDC, 110/220 VAC power supply • Stainless steel U-bolts and mounting bracket for amp • Installation Manual The following options are also available and may be ordered separately: CAB-DC DC power cable with 2.1mm plug to 3 foot long flying lead. Used when the customer provides his own 12 VDC power for the DC injector or amp. Dual-DC Option to add second power jack on DC injector to enable one 12 VDC PS that comes with the amp to power both the Injector and the radio or AP. (Requires a DC jumper cable.) DC-2.1-2.1 DC jumper cable that connects a radio modem or Access Point to the second DC power jack on the DC injector box. Radio devices must have a 2.1 mm ID power jack and operate on 12 VDC. DC-2.1-2.5 DC jumper cable used for radios and Access Points that have a 2.5 mm ID barrel jack. Close up of the bracket and mounting hardware attached to the amplifier. IMPORTANT: Only mount the amplifier with the connectors facing downward. Do not mount it with the connectors facing sideways or upwards which will void the warranty.
55.0 Installation and Cabling Instructions FCC NOTICE In order to comply with FCC Part 15 rules, the proper version of the amp must only be used in systems that have been FCC certified. Appendix B of this manual lists some of these certified systems. The system must be professionally installed to ensure compliance with the Part 15 certification. It is the responsibility of the professional installer to ensure that certified systems be deployed in the United States (or where FCC rules apply). The use of the amplifier in any other combination (such as co-located antennas transmitting the same information) is expressly forbidden in accordance with FCC rules CFR47 Part 15.204. Our web site (www.ydi.com) presents information on other YDI systems currently certified by the FCC. Several key factors unique to the particular installation determine the power level at the input of the amplifier. The most important consideration is the cable loss in the transmission cable between the radio and the pole-mounted amplifier. It is imperative that the Professional Installer be knowledgeable about these and other factors when installing the system. If you or your installer are not familiar with determining power levels within the transmission system, YDI engineers will assist you in planning your system including selecting the proper cable and antenna requirements. SAFETY NOTICE This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment when installed as directed. This equipment should be installed and operated with fix-mounted antennas that are installed such that the main lobe(s) of these antennas will have a minimum of 2 meters of separation distance between the antenna and all persons during normal operation. The amplifier can be mast-mounted using the steel U-bolt included with the unit. Refer to Section 11.0 for a cabling diagram. In outdoor applications, the amplifier must be installed with the connectors facing downward. Use an open-end wrench to carefully tighten the bolts using the included nuts. Take care not to over-tighten the bolts. Alternatively, the amplifier can be mounted to a flat surface using any of the mounting holes on the brackets mounting flanges. However, for maximum reliability, the connectors should be facing downward. It is imperative to waterproof the RF connectors on the amplifier. We recommend that you do not seal the connectors until after all system tests have been performed. Ensure that a high quality weather resistant electrical tape and/or another water sealant method is used. Silicon sealants are not recommended since they are difficult to work with, do not ensure a 100% waterproofing of the connectors and are hard to remove if ever necessary.
6The picture to the left shows the amplifier in typical installation shown with the YDI Model PT2421 Grid Dish antenna vertically polarized. The location on the mast where the amplifier is mounted is not important provided that the connectors face downward. (Note that when this picture was taken, the connectors were not taped yet nor was the cable secured to the mast.) Also, there is no need to plug or fill any of the holes on the back of the amplifier enclosure. The housing is designed such that these holes do not penetrate the inside of the waterproof seal even though an initial inspection might make you think otherwise. If the tower or mast is adequately grounded and the U-bolt makes good electrical connection to it, then there is no need to provide additional grounding to the amplifier enclosure. The DC Power Injector is not in a waterproof enclosure and must be protected from the weather. It can be permanently mounted to a surface using the mounting flanges. If the Injector is not mounted to a well-grounded metal plate or bulkhead, then a separate ground strap will be needed to connect to the grounding stud on the Injector. Refer to Section 11.0, Typical Installation Detail, for a drawing that outlines more information about the installation. 6.0 Amplifier Connections and Indicators CAUTION: Use only high quality N-type connectors. Do not use PL259 “CB” type UHF connectors. Doing so will ruin the N-Female jacks and void your warranty. Transmit LED: This LED glows RED when the amp has switched to the transmit mode. This occurs when the amp detects RF power at the jack labeled “To DC Injector”. (See Section 10 Operation for more information.) Receive LED: This LED glows GREEN in the receive mode when DC power is applied to the amplifier. It is goes off when the amp is in the transmitting mode. DC Injector Connection: This N-type female connects to the DC Power Injector via the transmission cable. The length of this cable will determine the type of cable that should be used. See the installation diagram and the Appendix for more information. Antenna Connection: This N-type female connects to the antenna with a short length of low-loss coax cable.
77.0 DC Power Injector Operation A DC Power Injector is an in-line device that “injects” the DC power necessary to operate the amplifier onto a transmission line. This allows the coax cable to carry both RF signals and DC power to the mast-mounted amplifier. This precludes the need to run a separate power cable to the remote mounted amplifier. When grounded to a good earth ground through either the grounding stud or mounting flange, the DC Injector will provide maximum lightning protection to your radio modem, wireless LAN card or Access Point. 8.0 DC Power Injector Connections and Indicators Red Transmit LED: This LED glows RED when the amplifier goes into transmit amplification mode. The Remote Transmit LED is controlled by unique circuitry, which actually detects changes in the DC current traveling through the transmission line to the amplifier. When the LED flashes, you know that the remote pole amplifier is going into transmit mode. Green Receive LED: This LED glows GREEN when DC power is applied to the amplifier and it goes into receive mode. When toggling between transmit and receive, the LED will glow slightly dimmer. “To Radio” Connection: This N-type female connects to the radio via a short jumper cable. “To Amplifier” Connection: This N-type female connects to the amplifier on the mast using the coax transmission line. 12 VDC: This is the DC power input for the injector and is a standard 2.1 mm barrel jack. +12VDC, center pin positive. AUX 12VDC: (Optional) This jack parallels the 12 VDC power jack. It can be used to provide 12 VDC to the radio modem or Access Point using a short DC jumper cable. The standard DC power supply that comes with the amplifier kit can be used to power both it and the amplifier/DC Injector provided that the radio device operates on 12 VDC and draws less then 600 ma. This extra jack is installed when the DC-INJ-DUAL option is ordered. 9.0 Power Supply The AMP2440 kit comes with a 100 to 240 VAC power supply that has a standard 2.1 mm barrel plug [center pin positive (+) tip and outer ring negative (-)]. Although normally supplied with a power supply, any 12 Volt DC, 1 amp (or greater) regulated power supply can be used. The amplifier can operate from 11 to 14 VDC enabling battery or vehicle operation as well. The DC power input is diode protected to prevent damage caused by reverse polarity input voltages as well as by a TVS to protect it and the amplifier from over-voltage surges.
810.0 Operation The unit operates automatically and there are no user adjustments required. The amplifier is only intended for use with 2.4 GHz radio modems that alternate between transmit and receive in the same radio channel. These are referred to as Time Division Dultiplex (TDD) devices. A typical example is an 802.11 WLAN card or Access Point. These modems “ping-pong” back and forth between transmit and receive so quickly during normal operation that both the TX and RX LEDs will appear to be lit simultaneously. In fact, they are turning on and off so quickly that they appear to be on all the time. You can tell the duty cycle of one of these LEDs by their brightness. The amplifier will not work with radio modems or wireless bridges that are band-split true full duplex devices. The amplifier provides for linear amplification for transmit output powers up to at least 400 mW. This is important for Direct Sequence Spread Spectrum (DSSS) radios, especially 802.11 devices. If you drive the amplifier so hard as to exceed the rated output power, the amplifier will start to go into compression. This will result in raising the sidebands and create interference on adjacent radio channels. The FCC Certification for this amplifier is for +24 dBm (250 mW) output, which requires the input to not exceed +10 dBm (10 mW). For Frequency Hopping Spread Spectrum radio devices, versions of the amplifier are available that have the output power limited to 250, 400 or 500 mW as specified in the FCC certified system. These amplifiers should not be used with DSSS radios since the transmit power limiting mechanism in the amplifier will cause it to go into compression when their respective clamped output levels are reached. 11.0 Typical Amplifier Installation Details The diagram that follows on the next page illustrates the typical AMP2440 amplifier installation.
9
10APPENDIX A Table A - Conversions from dBm to Watts dBm Watts dBm Watts 0 1.0 mW 26 400 mW 1 1.3 mW 27 500 mW 2 1.6 mW 28 640 mW 3 2.0 mW 29 800 mW 4 2.5 mW 30 1.0 W 5 3.2 mW 31 1.3 W 6 4.0 mW 32 1.6 W 7 5.0 mW 33 2.0 W 8 6 mW 34 2.5 W 9 8 mW 35 3.0 W 10 10 mW 36 4.0 W 11 13 mW 37 5.0 W 12 16 mW 38 6.0 W 13 20 mW 39 8.0 W 14 25 mW 40 10 W 15 32 mW 41 13 W 16 40 mW 42 16 W 17 50 mW 43 20 W 18 64 mW 44 25 W 19 80 mW 45 32 W 20 100 mW 46 40 W 21 128 mW 47 50 W 22 160 mW 48 64 W 23 200 mW 49 80 W 24 250 mW 50 100 W 25 320 mW 60 1000 W Table B - Typical Cable Attenuation Values Cable Type Attenuation per 100 ft at 2.4 GHz (dB) Belden 9913 8.0 LMR 200 16.8 LMR 240 12.9 LMR 400 6.9 LMR 600 4.4 1/2” LDF 3.9 1/2” Superflex 6.1 3/8” LDF 5.9 3/8” Superflex 6.8 1/4” Superflex 9.8 *Values are approximate. Consult the cable manufacturers for exact specifications.
11APPENDIX B FCC Part 15 Certified Systems FCC certified systems consist of: • A2440-xxF amplifier, DC Injector and 12 VDC Power supply • Orinoco/Agere WLAN card with the FCC ID#: IMRWLPCE24H • Outdoor Antenna • Coax cable (See Table D) • Consult the YDI web site for the most current product and certification information www.ydi.com Table A - Agere Authorized Antennas Model Antenna Type Antenna Gain (dBi) Max EIRP (dBm) MPE Distance (cm) Lucent AOU24-DI-24 Grid Dish Antenna 24 48 71 YDI PT2424 Grid Dish Antenna 24 48 71 YDI PT2421 Grid Dish Antenna 21 45 50 YDI A2.45FP18 Flat Panel Antenna 18 42 36 YDI A2.45FP15 Flat Panel Antenna 15 39 25 YDI A2.45FP12 Flat Panel Antenna 12 36 20 YDI A2.45LP17 Long Panel Antenna 17 41 32 YDI A2.45LP14 Long Panel Antenna 14 38 23 YDI HP90-16 Long Panel Antenna 16 40 32 YDI HP90-13 Long Panel Antenna 13 37 23 YDI A2412 Omni Antenna 12 36 20 YDI A2410 Omni Antenna 10 34 20 Lucent AOU24-OD-10 Omni Antenna 10 34 20 YDI SF-245 Omni Antenna 7.4 32 20 YDI A2408 Omni Antenna 8 32 20 Lucent XE 155845 Omni Antenna 6 30 20 YDI MAG-2400 Omni Antenna 5 29 20 YDI FP12A Amplified Flat Panel Antenna 12 36 20 YDI FP18A Amplified Flat Panel Antenna 18 42 36 FCC ID#: NM5-LUC2400E
12APPENDIX B (Continued) FCC Part 15 Certified Systems FCC certified systems consist of: • A2440-xxF amplifier, DC Injector and 12 VDC Power supply • Agere WLAN card, PART#: 012699 • Outdoor Antenna • Coax cable (See Table D) • Consult the YDI web site for the most current product and certification information www.ydi.com Table B - Agere Short Card Authorized Antennas Model Antenna Type Antenna Gain (dBi) Max EIRP(dBm) MPE Distance (cm) Lucent AOU24-DI-24 Grid Dish Antenna 24 48 71 YDI PT2424 Grid Dish Antenna 24 48 71 YDI PT2421 Grid Dish Antenna 21 45 50 YDI A2.45FP18 Flat Panel Antenna 18 42 36 YDI A2.45FP15 Flat Panel Antenna 15 39 25 YDI A2.45FP12 Flat Panel Antenna 12 36 20 YDI A2.45LP17 Long Panel Antenna 17 41 32 YDI A2.45LP14 Long Panel Antenna 14 38 23 YDI HP90-16 Long Panel Antenna 16 40 32 YDI HP90-13 Long Panel Antenna 13 37 23 YDI A2412 Omni Antenna 12 36 20 YDI A2410 Omni Antenna 10 34 20 Lucent AOU24-OD-10 Omni Antenna 10 34 20 YDI A2408 Omni Antenna 8 32 20 Lucent XE 155845 Omni Antenna 6 30 20 Lucent AOU-WA-12-B Wide Angle Antenna 12 36 20 Lucent AOU-WA-12-A Wide Angle Antenna 12 36 20 YDI FP12A Amplified Flat Panel Antenna 12 36 32 YDI FP18A Amplified Flat Panel Antenna 18 42 36 FCC ID#: A2400S
13APPENDIX B (Continued) FCC Part 15 Certified Systems FCC certified systems consist of: • A2440-xxF amplifier, DC Injector and 12 VDC Power supply • Nokia C111 WLAN card with the FCC ID#: ORE-C110-C111 • Outdoor Antenna • Coax Cable (See Table D) • Consult the YDI web site for the most current product and certification information www.ydi.com Table C - Nokia Authorized Antennas Model Antenna Type Antenna Gain (dBi) Max EIRP (dBm) MPE Distance (cm) YDI PT2424 Grid dish Antenna 24 48 71 YDI PT2421 Grid dish Antenna 21 45 50 YDI A2.45FP18 Flat Panel Antenna 18 42 36 YDI A2.45FP15 Flat Panel Antenna 15 39 25 YDI A2.45FP12 Flat Panel Antenna 12 36 20 YDI A2.45LP17 Long Panel Antenna 17 41 32 YDI A2.45LP14 Long Panel Antenna 14 38 23 YDI A2412 Omni Antenna 12 36 20 YDI A2410 Omni Antenna 10 34 20 YDI A2408 Omni Antenna 9 33 20 YDI FP12A Amplified Flat Panel Antenna 12 36 20 YDI FP18A Amplified Flat Panel Antenna 18 42 36 Note: 1. MPE distance figures are based on a conservative “worst case” prediction, i.e. +24 dBm into antenna using formula S=EIRP/(4piR2) and no calculation for duty factor. In practice the minimum distance will be much shorter. 2. The minimum MPE distance has been calculated for the maximum allowed Power Density (S) limit of 1.0 mW/cm2 in the Frequency range 1500-100,000 MHz for uncontrolled environments (Ref.2). Reference: 1. FCC Part 15, sub-clause 15.247 (b)(4) 2. FCC OET Bulletin 65, edition 97-01 3. FCC Supplement C to OET Bulletin 65, edition 97-01 FCC ID#: NM5-C111E
14APPENDIX B (Continued) Table D - Authorized Cables with Minimum Lengths Cable Type Minimum Length/Loss Max Recommended Lengths RG58/U 19 Feet/ 3.4 dB 40 Feet LMR 195 19 Feet/ 3.4 dB 40 Feet LMR200 20 Feet/ 3.4 dB 50 Feet LMR240 25 Feet/ 3.3 dB 65 Feet LMR400 50 Feet/ 3.4 dB 100 Feet LMR500 60 Feet/ 3.5 dB 140 Feet LMR600 80 Feet/ 3.5 dB 150 Feet LMR900 120 Feet/ 3.5 dB 250 Feet LMR1200 150 Feet/ 3.4 dB 350 Feet LMR1700 200 Feet/ 3.4 dB 480 Feet NOTE: This table is for reference only. In order to comply with FCC Part 15 Certification, the installer must insure that actual coax cable used between the DC injector and the amplifier has at least 3.3 dB of insertion loss. CAUTION: If the power output from the amplifier exceeds +24 dBm or the antennas used are in excess of 24 dBi gain, the FCC regulatory limits specified in Part 15.247 (b)(3)(i) could be exceeded.
15 APPENDIX C Calculating Input Power The following information explains how to calculate the input power to the amplifier for your configuration. 1. Using Appendix A, Table A, convert the output power of the radio modem from Watts (or milliWatts) to dBm. The Model AMP2440 amplifier is optimized to work with input powers between 3.2 mW (+5 dBm), and 10 mW (+10 dBm). 2. Calculate the cable attenuation for your installation. Determine the attenuation for the length of your cable at 2.4 GHz. Use the cable manufacturer’s specifications or, for convenience, refer to Appendix A, Table B for typical values. For example, Table B shows that typical attenuation for LMR-400 is about 6.9 dB per 100 foot at 2.4 GHz. Add 1.7 dB to that figure for miscellaneous losses for the connector, adaptor cable and DC injector. Subtract total attenuation from the radio’s transmit power. 3. Calculate the maximum power that can be expected at the amplifier when mounted on the pole as follows: Radio output (dB) - Cable loss (dB) - Miscellaneous Loss = Signal level at AMP2440 input (dBm) For example, a radio with 32mW (+15 dBm) output and 50 feet of LMR400 (about 3.4 dB of loss) would have the following input level to the amplifier: +15 dBm – 3.4 dB – 1.7dB = +9.9 dBm approx. +10dBm (10 mW) Using a standard amplifier with 14 dB of linear transmit power gain, the output power is calculated as follows: +10.0 dBm + 14 dB gain = +24 dBm output power (250 mW) If the input to the amplifier exceeds +10 dBm (10 mW) according to your calculations, an attenuator pad will be necessary between the modem and the DC injector. You can also order a special version of the amplifier from YDI that will accept higher transmit input power. NOTE: Never put attenuator pads between the cable, DC injector and amplifier since there is a +12V DC voltage on the cable. This will prevent DC power from reaching the amplifier and also damage the attenuator. A longer cable or one with higher loss could be used. Effective Isotropic Radiated Power (EIRP): EIRP is defined as the sum of the power feeding an antenna and the gain (in dBi) of that antenna. For example, with 250 mW (+24 dBm) of power into a 24 dBi gain grid dish antenna (such as the YDI PT2424), the EIRP would be: +24 dBm + 24 dB = 48 dBm or 64 watts EIRP

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