DATA S H E E T HIGH POWER TRAVELING WAVE TUBE FOR COMMUNICATIONS LD7263 14 GHz, 750 W CW, CONDUCTION COOLING, HIGH POWER GAIN GENERAL DESCRIPTION The NEC LD7263 is a PPM-focused traveling wave tube designed for use as final amplifiers in the earth-tosatellite communications transmitter. This is capable of delivering an output power of 750 W over the range of 1 3.75 to 14.5 GHZ and provides a power gain of more than 47 dB at 750 W Ievel. Furthermore, this is of rugged and reliable design offering long-Iife service. FEATURES ™ Lightweight, Compact and Efficient The tube has dual-depressed collectors and designed to operate at high efficiency across the power output range. It features state-of-the-art techniques to optimize size and efficiency. ™ Low Distortion Distortion is a very important factor in multiplex digital signals transmission. NEC has developed techniques for the correction of non-linear distortion and phase generated in a TWT. As a result, the TWT has an optimum performance across a broad power range and is ideally suited for multi-carrier transmission systems. ™ Simple Cooling System The tube is conduction cooled, so that the cooling system is simplified. ™ Rugged Construction The power gain is designed to be rugged, therefore it is suitable for transportable systems. ™ Long Life and High Stability The tube employs an advanced impregnated cathode with a low operating temperature for long life. ™ Micro-discharge Free The tube is carefully designed to be free from microdischarge in the electron gun for long term operation, therefore it is suitable for digital communication service. For safe use of microwave tubes, refer to NEC document “Safety instructions to all personnel handling electron tubes” (ET0048EJ∗V∗UM00) The information in this document is subject to change without notice. Document No. ET0479EJ1V0DS00 Date Published September 1999 M Printed in Japan © 1999 LD7263 GENERAL CHARACTERISTICS ELECTRICAL Frequency ……………………………………………… 13.75 to 14.5 GHz Output Power ………………………………………… 750 W Heater Voltage ………………………………………… 6.3 V Heater Current ………………………………………… 1.4 A Type of Cathode ……………………………………… Indirectly heated, Impregnated Cathode Warm-up Time …………………………… 180 s MECHANICAL Dimensions …………………………………………… See Outline Weight ………………………………………………… 3.5 kg approx. Focusing ……………………………………………… Periodic Permanent Magnet Mounting Position …………………………………… Any Electrical Connections ……………………………… Flying Leads RF Connections Input ………………………………………………… Type SMA Female Output ……………………………………………… WR75, UBR-120 Flange Cooling ………………………………………………… Conduction ABSOLUTE RATINGS (Note 1, 2 and 3 ) ELECTRICAL Heater Voltage ……………………………………… Heater Surge Current …………………………… Heater Current ……………………………………… Heater Warm-up Time …………………………… Helix Voltage ……………………………………… Helix Current ……………………………………… Collector-1 Voltage ………………………………… Collector-1 Current ………………………………… Collector-2 Voltage ………………………………… Collector-2 Current ………………………………… RF Drive Power …………………………………… Load VSWR ………………………………………… Min. 6.0 – – 180 10.2 – 5.3 – 2.3 – – – Max. 6.6 3.0 2.0 – 11.7 15.0 6.8 320 3.4 450 15 1.5 : 1 Unit V A A s kV mA kV mA kV mA dBm – Min. –40 –50 Max. +105 +85 Unit ˚C ˚C ENVIRONMENTAL Base Plate Temperature ………………………… Storage Temperature ……………………………… 2 DATA SHEET ET0479EJ1V0DS00 LD7263 TYPICAL OPERATION (Note 2, 3, 4 and 5) Unit Frequency …………………………………………… 14.25 GHz Output Power ……………………………………… 780 W Heater Voltage ( Note 4 ) ………………………… 6.3 V Heater Current ……………………………………… 1.4 A Collector Voltage-1 ………………………………… 6.0 kV Collector Current-1 ………………………………… 275 mA Collector Voltage-2 ………………………………… 2.9 kV Collector Current-2 ………………………………… 132 mA Cathode Current …………………………………… 410 mA Helix Voltage ……………………………………… 11.0 kV Helix Current ……………………………………… 3.0 mA Power Gain 58 dB (SSG) ………………………… (LSG) ………………………… 53 dB Gain Variation at 75 W ……………………… 1.0 dB/60MHz Gain Slope at 75 W ……………………… 0.01 dB/MHz at 75 W ……………………… 1.0 deg./dB at 750 W ……………………… 5.0 deg./dB 3rd Order Intermodulation ……………………… –31 dBc AM-PM Conversion (two equal carriers, 75 W total) Spurious …………………………………………… –60 dBc Noise Figure ………………………………………… 28 dB Overall Efficiency ………………………………… 37.6 % Note 1 : Absolute rating should not be exceeded under continuous or transient conditions. A single absolute rating may be the limitation and simultaneous operation at more than one absolute rating may not be possible. Note 2 : The tube body is at ground potential in operation. Note 3 : All voltages are referred to the cathode potential except the heater voltage. Note 4 : The optimum operating parameters are shown on a test performance sheet for each tube. Note 5 : These characteristics and operating values may be changed as a result of additional information or product improvement. NEC should be consulted before using this information for equipment design. This data sheet should not be referred to a contractual specification. DATA SHEET ET0479EJ1V0DS00 3 LD7263 LD7263 OUTLINE (Unit in mm) 8 - φ 10 COUNTER BORING RF OUTPUT WR75. FLANGE UBR-120 WITH No. 6-32 UNC-2B THREADED HOLES 71 ± 1.0 96 MAX. 55.88 ±0.2 55 NOM. 420 MAX. 303.5 ± 2.0 (127) 102.85 ± 0.6 150 NOM. 33 45.35 ± 0.2 25.4 ± 0.2 95.25 ± 0.2 139.7 ± 0.2 203.2 ± 0.2 266.7 ± 0.2 330.2 ± 0.2 50.8 ± 0.2 12.7 No.6-32 UNC-28 × 9 DP NEAR AND FARSIDE RF INTPUT TYPE SMA FEMALE 16 - φ 4.2 +0.4 0 38 MAX. 6±0.3 45.72 ±0.2 45 NOM. 55.5 MAX. LEAD COLOR 4 LEAD CONNECTIONS LENGTH BROWN HEATER 500 mm MIN. YELLOW HEATER-CATHODE 500 mm MIN. ORANGE COLLECTOR-1 500 mm MIN. BLUE COLLECTOR-2 500 mm MIN. GREEN HELIX (GROUND) 500 mm MIN. DATA SHEET ET0479EJ1V0DS00 LD7263 DATA SHEET ET0479EJ1V0DS00 5 LD7263 No part of this document may be copied or reproduced in any form or by any means without the prior written consent of NEC Corporation. NEC Corporation assumes no responsibility for any errors which may appear in this document. NEC Corporation does not assume any liability for infringement of patents, copyrights or other intellectual property rights of third parties by or arising from use of a device described herein or any other liability arising from use of such device. No license, either express, implied or otherwise, is granted under any patents, copyrights or other intellectual property rights of NEC Corporation or others. While NEC Corporation has been making continuous effort to enhance the reliability of its electronic components, the possibility of defects cannot be eliminated entirely. To minimize risks of damage or injury to persons or property arising from a defect in an NEC electronic component, customers must incorporate sufficient safety measures in its design, such as redundancy, fire-containment, and anti-failure features. NEC devices are classified into the following three quality grades: “Standard”, “Special”, and “Specific”. The Specific quality grade applies only to devices developed based on a customer designated “quality assurance program” for a specific application. The recommended applications of a device depend on its quality grade, as indicated below. Customers must check the quality grade of each device before using it in a particular application. Standard: Computers, office equipment, communications equipment, test and measurement equipment, audio and visual equipment, home electronic appliances, machine tools, personal electronic equipment and industrial robots Special: Transportation equipment (automobiles, trains, ships, etc.), traffic control systems, anti-disaster systems, anti-crime systems, safety equipment and medical equipment (not specifically designed for life support) Specific: Aircrafts, aerospace equipment, submersible repeaters, nuclear reactor control systems, life support systems or medical equipment for life support, etc. The quality grade of NEC devices is "Standard" unless otherwise specified in NEC's Data Sheets or Data Books. If customers intend to use NEC devices for applications other than those specified for Standard quality grade, they should contact an NEC sales representative in advance. Anti-radioactive design is not implemented in this product.