Application & Brief The Becker UHF Bi-Directional Amplifier is typically used in Mining, Shipping, Tunnelling, Motorway and In-Building radiating cable systems to compensate for Leaky Feeder Cable longitudinal losses in both directions simultaneously. Becker BDA specifications are optimally suited to maximize these performance criteria. The BDA serves to maintain the strength of RF signal levels along the Leaky Feeder coaxial cable. The amplifier is unique in that it offers the lowest possible noise contribution to an already weak RF carrier when operating in collocation with a strong carrier. The connectors of the inline amplifiers have been designed for ease of connection making installation and repair as convenient as possible. The Power Source required from the Leaky Feeder cable is 5V to 17Vdc. The most important performance criteria of a BDA are: Channel capacity - Number of simultaneous voice and data Channel quality (clear voice channels, data channel, integrity). Channel isolation (Freedom from intermodulation distortion). Distance achievable away from the cable. Reliability and Mean Time Between Failure channels. Becker BDA specifications are optimally suited to maximize these performance criteria. Intrinsically Safe The UESM211 has the following safety description and is applicable to the Headend and Tunnel connectors: Ui = 17V Ii = 1.08A Pi = 12.75W Li = 22 uh Ci = 116.6 nf The BDA has two RF connections, which are the same IS circuit and can be powered from either connectors. The safety description of the power connected to the one side of the BDA are the output parameters of the other connector, except the terminal parameters Ci and Li of the BDA have also to be taken into account. Purchase Contact Details Becker Electronics CNR Freda and CR Swart Drive Randburg Johannesburg South Africa 2169 Tel: +27 11 801-5900 Fax: +27 11 793-7900 Website: www.becker-mining.com Email: sales@beckerelectronics.co.za DISCLAIMER All information given in this datasheet is correct to the best of our knowledge, but the company reserves the right to make alterations and amendments to the detailed specification at its discretion. Page 1 of 5
Functional Features Technical Features DC Power Voltage status indicators of front panel DC Power Amplifier Current consumption indicators on front panel Downlink signal strength indicators to ensure line spacing is correct. Uplink AGC ON indication to ensure up-link is working correctly. Integrated Cable Length Compensation (CLC) to simulate additional cable lengths as necessary. Optimized noise performance in VHF Leaky Feeder systems. Carefully distributed amplification using low voltage GaAs devices in both directions to optimize overall figure under dynamic (Small and Large Simultaneously) conditions. Protection: Transorb Diodes that clamp transient energy at defined voltage levels. Protection: Switchmode Voltage Regulator which reduces the applied voltage on the Leaky Feeder line down to the internally required 3 volts. Protection: A polyswitch to protect the amplifier circuitry in the event of excess current drain Interpretation Of Bi-Directional Amplifier Specifications BDA's are inserted into the Leaky Feeder cables (transmission lines) to compensate for the longitudinal losses through the cable. Leaky Feeder gradually radiates a portion of the radio power contained in the cab replenished by the BDA's. As such, their primary electrical specifications are based around the following attributes: SELECTIVITY - Ability to pass wanted frequencies and reject interferers GAIN RESPONSE RIPPLE - Deviation of Gain from centre of pass band. OPEN LOOP GAIN - Ability to amplify small signals to their original strength OUTPUT POWER SET POINT - Nominal radio signal strength amplifiers strives to retain at output NOISE FIGURE - BDA's contribution to overall system noise floor CHANNEL CAPACITY - Number of simultaneous radio communication channels Performance Specifications Frequency range Voice/ Data Channel Capacity Down Link Open Loop Gain Gain Response Ripple Downlink Nominal Output Setpoint Typical LED LOW Threshold Typical LED GOOD Threshold Typical LED HIGH Threshold Typical LED HIGH HIGH Threshold Up Link Open Loop Gain Gain Response Ripple Uplink Nominal Output Setpoint Typical AGC LED Threshold Operating Voltage Current Requirement @ 12VDC Approved Explosion Protection rating (ia) Inspection Authority Certificate (ia) Through current capacity CLC 3dB Attenuated Gain (Up & Down) CLC 6dB Attenuated Gain (Up & Down) CLC 9dB Attenuated Gain (Up & Down) Base to Handheld 460 MHz 470 MHz (Down-link) Handheld to Base 435 MHz 445 MHz (Up-link) 80 Channels Up 80 Channels Down 22 db min 2 db maximum 0dBm -22dBm -18dBm -15dBm -10dBm 220 db min 2 db maximum 0dBm -18dBm 5V to 17Vdc 250mA max Ex GI ia SIRA 04ATEX2165X 3.0A max. 19dB typical 16dB typical 13dB typical Page 2 of 5
Typical Response Curve Interface & Control The CLC feature allows the installation technician to simulate an additional length of cable on the Left Hand Side (Base Station side) of the Becker Electronics Bi-Directional Amplifiers. The variable attenuator is there to set the measure of CLC (cable length compensation). At position 0 (zero) it has no compensation. For every step up (1 to F) it adds an additional approximate 0.5dB compensation to the main line. The AGC takes care of any further errors. Environmental Specifications Operating Temperature Limits -10 C to +55C Storage Temperature Limits -40 C to + 65 C Operating Altitude Up to 5500m ASL Operating Humidity 10 to 85% (Non Condensing) Protection Class IP66 according to EN60529 Impact Resistance 7Nm Body Only Not indicator lights Flammability UL94 V-O Toxicity Halogen and Cadmium Free Electromagnetic Interference (EMI) FCC Emissions Class A (Industrial) CE Emissions Class A (Industrial) Page 3 of 5
Mechanical Specifications Width (Excluding mounting brackets) Height (Excluding mounting brackets) Depth (Excluding mounting brackets) Weight 230mm 75mm 61mm 1.24kg Principal Materials Finish Gasket Mounting Options Enclosure: Glass Reinforced Polyester GRP Connectors: Electroplated Brass Thermoplastic polymer glass fiber Natural Grey (Similar to RAL7001) Silicon rubber 4 holes M6 directly Internal Circuitry Page 4 of 5
Mechanical Drawing Ordering Information What s In The Box Part No: UESM 211 XXXXXX (Base Part No.) (Serial No) UHF Bi-Directional AMP Datasheet Test Results Sheet Page 5 of 5