APPLICATION NOTE A wide-band class-a linear power amplifier (174 230 MHz) with two transistors
CONTENTS 1 ABSTRACT 2 INTRODUCTION 3 DESIGN OF THE AMPLIFIER 4 ADJUSTMENTS OF THE AMPLIFIER 5 ASSEMBLING OF THE AMPLIFIER AND MECHANICAL DATA 6 MEASURED RESULTS 7 CONCLUSION 8 REFERENCES 1998 Mar 23 2
1 ABSTRACT For application in driver or final stages of TV-transposers in band III (174 230 MHz) a linear wideband power amplifier has been designed with 2 transistors, coupled by means of 3 90 hybrids. Each transistor is adjusted in class-a at V CE = 25 V and I C = 3.25 A. A demonstration model showed a peak sync output power of 40 W at a 3-tone I.M. distortion between 56 and 58. At this power level the cross-modulation varied from 6 to 7.5%. The power gain is between 8.35 and 8.6. 2 INTRODUCTION For application in T.V. transposers and transmitters for band III a wideband linear power amplifier has been designed with 2 transistors, coupled by means of 3 90 hybrids. Each transistor is adjusted in class-a at V CE =25V and I C = 3.25 A. 3 DESIGN OF THE AMPLIFIER For class-a operation the is specified at V CE = 25 V, I C = 3.25 A. The corresponding typical gain, input and load impedance are given below: Table 1 FREQ. (MHz) GAIN () INPUT IMPEDANCE (Ω) LOAD IMPEDANCE (Ω) 174 11.3 0.68 + j1.20 2.70 + j1.19 202 10.1 0.68 + j1.43 2.30 + j0.87 230 9.08 0.68 + j1.64 1.99 + j0.52 A computer-aided circuit design, carried out by Mr. Hilbers (Central Application Laboratory) indicated a gain of 9.1 ±0.1 and V.S.W.R. figures of 4.3 (170 MHz), 2.78 (202 MHz) and 1.18 at 230 MHz for a single amplifier. To obtain a high linear output and at the same time good input and output matching (V.S.W.R. 1.2) 3 90 hybrids are used. The reflected input power will be absorbed in the resistor, matching the isolated port (see Fig.1). There are some small differences (value and place of chip capacitors) between the theoretical design and practical circuit. For detailed information on computer-aided design see Refs 1 and 2. Mainly due to the insertion loss of the 3 hybrids the gain drops from 9 to 8.5. The transistors used in this particular amplifier are typical products, measured in a narrow band test amplifier and specified as follows: V CE =25V I C = 3.25 A T h =70 C 1998 Mar 23 3
Table 2 Transistor type Batch no. MD 8-14 no 5 MD 8-14 no 10 Vision frequency 224.25 MHz Output power (peak sync) 22.9 W 22.6 W Intermodulation product 55 55 Gain 9.03 9.11 4 ADJUSTMENTS OF THE AMPLIFIER The amplifier consists of two equal branches (see Fig.1) and both transistors are separately biased at V CE =25V, I C = 3.25 A. A schematic diagram and lay-out of the bias unit is given in Fig.2. Each branch was adjusted for maximum and flat gain by means of a high power sweep with a frequency range from 170 to 230 MHz. The output power of the amplifier was levelled at 40 W which means about 50% of the D.C. input power. After that, both branches are coupled by means of 3 90 hybrids, input and output matching of the complete amplifier are adjusted below a V.S.W.R. of 1.2 with the aid of capacitors C1-C2-C37-C38 as shown in Fig.1. 5 ASSEMBLING OF THE AMPLIFIER AND MECHANICAL DATA Due to the dimensions of the p.c. board (220 210 mm) 2 extruded blackened aluminium heatsinks (cat. no. 56293) are screwed together. The transistors are screwed on an aluminium plate (thickness 12 mm) which on its turn is screwed on the heatsink. Special attention has been paid to the surface finishing to keep the thermal resistance as low as possible. Figure 3 showed the p.c. board and lay-out of the amplifier. Dimensions: l = 224 mm w = 223 mm h = 113 mm. Weight: 7.5 kg. 6 MEASURED RESULTS Table 3 Frequency range 170 to 230 MHz Output power (peak sync) 30 W 40 W 50 W I.M. distortion 60 56 54 ; note 1 Cross modulation 3% 6/7.5% 10/15.5%; note 2 Output power for 1 gain 100 W compression Gain at 40 W output level 8.5 ±0.1 Input and output V.S.W.R. 1.2 Ambient temp. 25 C Heatsink temp. 65 C Transistor stud temp. 85 C Notes 1. Vision carrier 8, sound carrier 7, side signal 16, zero corresponds to peak sync level; f sound =f vision + 5.5 MHz, f sideband =f vision 1 MHz to f vision + 6 MHz. 2. Vision carrier 0, sound carrier 7 : voltage variation of sound carrier (%) when the vision carrier is switched from 20 to 0 ; f sound =f vision + 5.5 MHz. 1998 Mar 23 4
In Fig.4 the typical results of crossmodulation and intermodulation measurements on a demonstration amplifier have been given. Figures 5 and 6 show the S-parameters of the complete amplifier. The measuring set-up is depicted in Fig.7. 7 CONCLUSION Two transistors, coupled by means of 3 90 hybrids, can deliver an output power of typ. 40 W with an associated gain of 8.5. Required D.C. input power approx. 165 W. Using a high power sweep with adjustable transistor output power levelling provides a suitable method to adjust a linear wideband power amplifier. 8 REFERENCES Ref. 1: G.L. Matthaei Tables of Chebyshev Impedance Transforming Networks of Low-Pass Filter Form. Proceedings of the IEEE August 1964, pp. 939 963. Ref. 2: A.H. Hilbers and M.J. Köppen A wide-band linear power amplifier (470 860 MHz) with two transistors BLW34. C.A.B. report ECO7901. 1998 Mar 23 5
This text is here in white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader.this text is here in _white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader.this text is here inthis text is here in white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader. white to force landscape pages to be... 1998 Mar 23 6 input C2 R1 C1 R2 in iso C3 0 H1 90 C5 L1 C6 C9 C10 L4 V b R3 C19 C14 handbook, full pagewidth C13 C27 L3 L7 L10 L13 L15 L19 L17,,,,,,, L9 V c C25 C26 C21 C31 C15 C22 C32 L21 C35 90 iso H2 0 in R5 R6 C38 C37 output Philips Semiconductors C4 C7 L2 C11 C16 C23 C33 L8 L11 L14 L16 L20 L5 L18 L22,,,,,,,,,, C36 C8 C12 C17 C24 C34 L12 L6 C28 C18 C29 R4 C20 C30 V b V c MGP988 Fig.1 Band III Class A linear power amplifier (170 230 MHz).
Table 4 Parts list: Band III class A linear power amplifier (170 230 MHz) C1 = C38 1.5 pf chip capacitor C2 = C3 = C4 = C37 5.6 pf chip capacitor C5 = C8 = C32 = C33 1.8 to 10 pf film dielectric trimmer (cat. no. 222280905002) C6 = C7 = C35 = C36 220 pf chip capacitor C9 = C10 = C11 = C12 18 pf chip capacitor C13 = C18 = C27 = C28 1000 pf chip capacitor C14 = C15 = C16 = C17 100 pf chip capacitor C19 = C20 = C26 = C29 330 nf metallized film capacitor (cat. no. 222235225334) C21 = C23 68 pf chip capacitor C22 = C24 56 pf chip capacitor C25 = C30 10 µf (40 V) electrolytic capacitor (cat. no. 222212117109) C31 = C34 22 pf chip capacitor (chip capacitors: ATC type 100B C MSX 500) R1 = R2 = R5 = R6 100 Ω power metal film resistor, PR52 type (cat. no. 232219231001) R3 = R4 10 Ω carbon resistor, CR68 type (cat. no. 23222141309) H1 = H2 3 90 coupler model no. 10262 3, range 125 250 MHz, Anaren Microwave Inc. L1 = L2 25 nh 2 turns enamelled Cu wire (1 mm); int. diam. 5 mm; length 5 mm; leads 2 3mm L3 = L6 90 nh 5 turns closely wound enamelled Cu wire (1 mm); int. diam. 4.5 mm; leads 2 9mm L4 = L5 60 Ω stripline; w = 2 mm; l = 30 mm L7 = L8 30 Ω stripline; w = 6 mm; l = 11 mm L9 = L12 20 nh Cu strip (1 mm); l = 17 mm; h = 5 mm; w = 4 mm L10 = L11 30 Ω stripline; w = 6 mm; l = 8 mm L13 = L14 30 Ω stripline; w = 6 mm; l = 14 mm L15 = L16 30 Ω stripline; w = 6 mm; l = 4 mm L17 = L18 22 nh 2 turns closely wound Cu wire (1.5 mm); int. diam. 4.5 mm; leads 2 3mm L19 = L20 30 Ω stripline; w = 6 mm; l = 6 mm L21 = L22 stripline; w = 3 mm; l = 15 mm The striplines are printed on double Cu-clad printed circuit board with epoxy fibre-glass dielectric (ε r = 4.5); thickness 1/16 inch. 1998 Mar 23 7
handbook, full pagewidth V s (+ 27 V) R5 D2 R1 R6 R7 C4 e b c TR1 BD136 C1 C2 D1 R2 R3 R8 C3 R9 V c V b V ce = 25 V,,,,, R4 R10 MGP997 handbook, full pagewidth 55 R5 C1 C2 R6 72 V s D1 D2 R1 R3 R7 C4 C3 R2 R8 R9 V c e c b V b R4 R10 MGP998 Fig.2 Class A bias circuit for a single transistor. 1998 Mar 23 8
Table 5 Parts list: Class A bias circuit for a single transistor R1 1 carbon resistor CR25 type R2 100 Ω preset potentiometer CTP10 type R3 10 Ω carbon resistor CR25 type R4 1000 Ω carbon resistor CR25 type R5 = R6 = R7 1.8 Ω rectangular wirewound resistor EH707 type R8 = R9 180 Ω carbon resistor CR25 type R10 33 Ω carbon resistor CR25 type C1 = C3 100 nf metallized film capacitor C2 100 pf ceramic capacitor C4 10 µf 40 V electrolytic capacitor D1 BZY 88 (3V3) D2 BY 206 T1 BD 136 1998 Mar 23 9
handbook, full pagewidth 220 210 MGP989 Fig.3 P.C. Board and 2 amplifier lay-out. 1998 Mar 23 10
16 handbook, full pagewidth MGP991 crossmod. (%) 12 0 7 V (%) P o sync = 50 W 20 8 40 W 4 30 W 0 168 175 182 189 196 203 210 217 f (MHz) 224 44 handbook, full pagewidth intermod. product () 46 intermod. product 8 16 0 = P o sync 7 MGP992 48 50 P o sync = 52 60 W 54 56 50 W 58 40 W 60 62 168 175 182 189 196 203 210 217 30 W f (MHz) 224 Vision carrier level: 20 /0. Sound carrier level: 7. Sync level: 0. Fig.4 Crossmodulation and intermodulation products of the 2 wideband Band III power amplifier. 1998 Mar 23 11
9 handbook, halfpage MGP993 () 8.5 8 S21 7.5 130 150 170 190 210 230 250 (MHz) a. Forward transducer gain. handbook, () halfpage 0 10 20 30 MGP994 V.S.W.R. 2 1.5 1.2 1.1 40 50 S11 60 130 150 170 190 210 230 250 (MHz) b. Input voltage standing wave ratio. Fig.5 2 wideband Band III power amplifier. 1998 Mar 23 12
handbook, () halfpage MGP995 0 10 20 30 40 50 S12 60 130 150 170 190 210 230 250 (MHz) a. Reverse transducer gain. handbook, () halfpage 0 10 20 30 MGP996 V.S.W.R. 2 1.5 1.2 1.1 40 50 S22 60 130 150 170 190 210 230 250 (MHz) b. Output voltage standing wave ratio. Fig.6 2 wideband Band III power amplifier. 1998 Mar 23 13
This text is here in white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader.this text is here in _white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader.this text is here inthis text is here in white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader. white to force landscape pages to be... 1998 Mar 23 14 POWER DIVIDER HP778D 6 DIRECT. COUPLER VAR. ATT. COAX SWITCH BAND III WIDEBAND POWER AMPLIFIER D.U.T. 2 COAX SWITCH handbook, full pagewidth 10 ATT. (100W) POWER DIVIDER HP778D CIRCULATOR RANGES: 170 to 200 MHz 190 to 230 MHz COAX SWITCH DIRECT. COUPLER ALC ATT. 6 AMPLIFIER 8554L SPECTRUM ANALYZER 20 ATT. 3-180 HYBRID VAR. ATT. 10 CD 50-4 HP435A WATT METER 20 ATT. 10 S.M.L.U. R.F. GEN. ATT. Philips Semiconductors SWOB III S.M.L.U. SWEEP SWEEP PM5171 ALC S.M.L.U. R.F. GEN. COAX DETECTOR 20 D.C. AMPLIFIER AMPLIFIER POWER SWEEP TEST SET-UP Fig.7 Test set up 2 Band III power amplifier. AMPLIFIER AMPLIFIER VAR. ATT. 10 VAR. ATT. 10 S.M.L.U. R.F. GEN. S.M.L.U. R.F. GEN. 170 to 230 MHz 3-TONE TEST SET-UP MGP990
a worldwide company Argentina: see South America Australia: 34 Waterloo Road, NORTH RYDE, NSW 2113, Tel. +61 2 9805 4455, Fax. +61 2 9805 4466 Austria: Computerstr. 6, A-1101 WIEN, P.O. Box 213, Tel. +43 160 1010, Fax. +43 160 101 1210 Belarus: Hotel Minsk Business Center, Bld. 3, r. 1211, Volodarski Str. 6, 220050 MINSK, Tel. +375 172 200 733, Fax. +375 172 200 773 Belgium: see The Netherlands Brazil: see South America Bulgaria: Philips Bulgaria Ltd., Energoproject, 15th floor, 51 James Bourchier Blvd., 1407 SOFIA, Tel. +359 2 689 211, Fax. +359 2 689 102 Canada: PHILIPS SEMICONDUCTORS/COMPONENTS, Tel. +1 800 234 7381 China/Hong Kong: 501 Hong Kong Industrial Technology Centre, 72 Tat Chee Avenue, Kowloon Tong, HONG KONG, Tel. +852 2319 7888, Fax. +852 2319 7700 Colombia: see South America Czech Republic: see Austria Denmark: Prags Boulevard 80, PB 1919, DK-2300 COPENHAGEN S, Tel. +45 32 88 2636, Fax. +45 31 57 0044 Finland: Sinikalliontie 3, FIN-02630 ESPOO, Tel. +358 9 615800, Fax. +358 9 61580920 France: 51 Rue Carnot, BP317, 92156 SURESNES Cedex, Tel. +33 1 40 99 6161, Fax. +33 1 40 99 6427 Germany: Hammerbrookstraße 69, D-20097 HAMBURG, Tel. +49 40 23 53 60, Fax. +49 40 23 536 300 Greece: No. 15, 25th March Street, GR 17778 TAVROS/ATHENS, Tel. +30 1 4894 339/239, Fax. +30 1 4814 240 Hungary: see Austria India: Philips INDIA Ltd, Band Box Building, 2nd floor, 254-D, Dr. Annie Besant Road, Worli, MUMBAI 400 025, Tel. +91 22 493 8541, Fax. +91 22 493 0966 Indonesia: see Singapore Ireland: Newstead, Clonskeagh, DUBLIN 14, Tel. +353 1 7640 000, Fax. +353 1 7640 200 Israel: RAPAC Electronics, 7 Kehilat Saloniki St, PO Box 18053, TEL AVIV 61180, Tel. +972 3 645 0444, Fax. +972 3 649 1007 Italy: PHILIPS SEMICONDUCTORS, Piazza IV Novembre 3, 20124 MILANO, Tel. +39 2 6752 2531, Fax. +39 2 6752 2557 Japan: Philips Bldg 13-37, Kohnan 2-chome, Minato-ku, TOKYO 108, Tel. +81 3 3740 5130, Fax. +81 3 3740 5077 Korea: Philips House, 260-199 Itaewon-dong, Yongsan-ku, SEOUL, Tel. +82 2 709 1412, Fax. +82 2 709 1415 Malaysia: No. 76 Jalan Universiti, 46200 PETALING JAYA, SELANGOR, Tel. +60 3 750 5214, Fax. +60 3 757 4880 Mexico: 5900 Gateway East, Suite 200, EL PASO, TEXAS 79905, Tel. +9-5 800 234 7381 Middle East: see Italy Netherlands: Postbus 90050, 5600 PB EINDHOVEN, Bldg. VB, Tel. +31 40 27 82785, Fax. +31 40 27 88399 New Zealand: 2 Wagener Place, C.P.O. Box 1041, AUCKLAND, Tel. +64 9 849 4160, Fax. +64 9 849 7811 Norway: Box 1, Manglerud 0612, OSLO, Tel. +47 22 74 8000, Fax. +47 22 74 8341 Philippines: Philips Semiconductors Philippines Inc., 106 Valero St. Salcedo Village, P.O. Box 2108 MCC, MAKATI, Metro MANILA, Tel. +63 2 816 6380, Fax. +63 2 817 3474 Poland: Ul. Lukiska 10, PL 04-123 WARSZAWA, Tel. +48 22 612 2831, Fax. +48 22 612 2327 Portugal: see Spain Romania: see Italy Russia: Philips Russia, Ul. Usatcheva 35A, 119048 MOSCOW, Tel. +7 095 755 6918, Fax. +7 095 755 6919 Singapore: Lorong 1, Toa Payoh, SINGAPORE 1231, Tel. +65 350 2538, Fax. +65 251 6500 Slovakia: see Austria Slovenia: see Italy South Africa: S.A. PHILIPS Pty Ltd., 195-215 Main Road Martindale, 2092 JOHANNESBURG, P.O. Box 7430 Johannesburg 2000, Tel. +27 11 470 5911, Fax. +27 11 470 5494 South America: Al. Vicente Pinzon, 173, 6th floor, 04547-130 SÃO PAULO, SP, Brazil, Tel. +55 11 821 2333, Fax. +55 11 821 2382 Spain: Balmes 22, 08007 BARCELONA, Tel. +34 3 301 6312, Fax. +34 3 301 4107 Sweden: Kottbygatan 7, Akalla, S-16485 STOCKHOLM, Tel. +46 8 632 2000, Fax. +46 8 632 2745 Switzerland: Allmendstrasse 140, CH-8027 ZÜRICH, Tel. +41 1 488 2686, Fax. +41 1 488 3263 Taiwan: Philips Semiconductors, 6F, No. 96, Chien Kuo N. Rd., Sec. 1, TAIPEI, Taiwan Tel. +886 2 2134 2865, Fax. +886 2 2134 2874 Thailand: PHILIPS ELECTRONICS (THAILAND) Ltd., 209/2 Sanpavuth-Bangna Road Prakanong, BANGKOK 10260, Tel. +66 2 745 4090, Fax. +66 2 398 0793 Turkey: Talatpasa Cad. No. 5, 80640 GÜLTEPE/ISTANBUL, Tel. +90 212 279 2770, Fax. +90 212 282 6707 Ukraine: PHILIPS UKRAINE, 4 Patrice Lumumba str., Building B, Floor 7, 252042 KIEV, Tel. +380 44 264 2776, Fax. +380 44 268 0461 United Kingdom: Philips Semiconductors Ltd., 276 Bath Road, Hayes, MIDDLESEX UB3 5BX, Tel. +44 181 730 5000, Fax. +44 181 754 8421 United States: 811 East Arques Avenue, SUNNYVALE, CA 94088-3409, Tel. +1 800 234 7381 Uruguay: see South America Vietnam: see Singapore Yugoslavia: PHILIPS, Trg N. Pasica 5/v, 11000 BEOGRAD, Tel. +381 11 625 344, Fax.+381 11 635 777 For all other countries apply to: Philips Semiconductors, International Marketing & Sales Communications, Building BE-p, P.O. Box 218, 5600 MD EINDHOVEN, The Netherlands, Fax. +31 40 27 24825 Internet: http://www.semiconductors.philips.com Philips Electronics N.V. 1998 SCA57 All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent- or other industrial or intellectual property rights. Printed in The Netherlands Date of release: 1998 Mar 23
SUNSTAR 商斯达实业集团是集研发 生产 工程 销售 代理经销 技术咨询 信息服务等为一体的高科技企业, 是专业高科技电子产品生产厂家, 是具有 10 多年历史的专业电子元器件供应商, 是中国最早和最大的仓储式连锁规模经营大型综合电子零部件代理分销商之一, 是一家专业代理和分銷世界各大品牌 IC 芯片和電子元器件的连锁经营綜合性国际公司, 专业经营进口 国产名厂名牌电子元件, 型号 种类齐全 在香港 北京 深圳 上海 西安 成都等全国主要电子市场设有直属分公司和产品展示展销窗口门市部专卖店及代理分销商, 已在全国范围内建成强大统一的供货和代理分销网络 我们专业代理经销 开发生产电子元器件 集成电路 传感器 微波光电元器件 工控机 /DOC/DOM 电子盘 专用电路 单片机开发 MCU/DSP/ARM/FPGA 软件硬件 二极管 三极管 模块等, 是您可靠的一站式现货配套供应商 方案提供商 部件功能模块开发配套商 商斯达实业公司拥有庞大的资料库, 有数位毕业于著名高校 有中国电子工业摇篮之称的西安电子科技大学 ( 西军电 ) 并长期从事国防尖端科技研究的高级工程师为您精挑细选 量身订做各种高科技电子元器件, 并解决各种技术问题 微波光电部专业代理经销高频 微波 光纤 光电元器件 组件 部件 模块 整机 ; 电磁兼容元器件 材料 设备 ; 微波 CAD EDA 软件 开发测试仿真工具 ; 微波 光纤仪器仪表 欢迎国外高科技微波 光纤厂商将优秀产品介绍到中国 共同开拓市场 长期大量现货专业批发高频 微波 卫星 光纤 电视 CATV 器件 : 晶振 VCO 连接器 PIN 开关 变容二极管 开关二极管 低噪晶体管 功率电阻及电容 放大器 功率管 MMIC 混频器 耦合器 功分器 振荡器 合成器 衰减器 滤波器 隔离器 环行器 移相器 调制解调器 ; 光电子元器件和组件 : 红外发射管 红外接收管 光电开关 光敏管 发光二极管和发光二极管组件 半导体激光二极管和激光器组件 光电探测器和光接收组件 光发射接收模块 光纤激光器和光放大器 光调制器 光开关 DWDM 用光发射和接收器件 用户接入系统光光收发器件与模块 光纤连接器 光纤跳线 / 尾纤 光衰减器 光纤适配器 光隔离器 光耦合器 光环行器 光复用器 / 转换器 ; 无线收发芯片和模组 蓝牙芯片和模组 更多产品请看本公司产品专用销售网站 : 商斯达中国传感器科技信息网 :http://www.sensor-ic.com/ 商斯达工控安防网 :http://www.pc-ps.net/ 商斯达电子元器件网 :http://www.sunstare.com/ 商斯达微波光电产品网 :HTTP://www.rfoe.net/ 商斯达消费电子产品网 ://www.icasic.com/ 商斯达实业科技产品网 ://www.sunstars.cn/ 微波元器件销售热线 : 地址 : 深圳市福田区福华路福庆街鸿图大厦 1602 室电话 :0755-82884100 83397033 83396822 83398585 传真 :0755-83376182 (0)13823648918 MSN: SUNS8888@hotmail.com 邮编 :518033 E-mail:szss20@163.com QQ: 195847376 深圳赛格展销部 : 深圳华强北路赛格电子市场 2583 号电话 :0755-83665529 25059422 技术支持 : 0755-83394033 13501568376 欢迎索取免费详细资料 设计指南和光盘 ; 产品凡多, 未能尽录, 欢迎来电查询 北京分公司 : 北京海淀区知春路 132 号中发电子大厦 3097 号 TEL:010-81159046 82615020 13501189838 FAX:010-62543996 上海分公司 : 上海市北京东路 668 号上海賽格电子市场 D125 号 TEL:021-28311762 56703037 13701955389 FAX:021-56703037 西安分公司 : 西安高新开发区 20 所 ( 中国电子科技集团导航技术研究所 ) 西安劳动南路 88 号电子商城二楼 D23 号 TEL:029-81022619 13072977981 FAX:029-88789382