NEC LD7262

DATA S H E E T
HIGH POWER TRAVELING WAVE TUBE
FOR COMMUNICATIONS
LD7262 SERIES
6 GHz, 750 W CW, CONDUCTION COOLING, HIGH POWER GAIN
GENERAL DESCRIPTION
The NEC LD7262 series of PPM focused traveling wave tubes are designed for final amplifier in the earth-tosatellite communication's transmitter.
These are capable of delivering an output power of 750 W over the range of 5.85 to 6.45 GHZ and an output
power of 700 W over the range of 5.85 to 7.1 GHZ With a power gain of more than 45 dB at any power level.
Furthermore, these are rugged and reliable design offering long life services.
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 pertormance 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. ET0475EJ1V0DS00 (1st edition)
Date Published September 1999 M
Printed in Japan
©
1999
LD7262 SERIES
GENERAL CHARACTERISTICS
ELECTRICAL
Frequency ……………………………………………… 5.85 to 6.45 GHz
5.85 to 7.1 GHz
Output Power ………………………………………… 750 W (5.85 to 6.45 GHz)
700 W (5.85 to 7.1 GHz)
Heater Voltage ………………………………………… 6.3 V
Heater Current ………………………………………… 1.6 A
Type of Cathode ……………………………………… Indirectly heated, Impregnated
Cathode Warm-up Time …………………………… 180 s
MECHANICAL
Dimensions …………………………………………… See Outline Drawing
Weight ………………………………………………… 4.0 kg approx.
Focusing ……………………………………………… Periodic Permanent Magnet
Mounting Position …………………………………… Any
Electrical Connections ……………………………… Flying Leads
RF Connections
Input ………………………………………………… SMA Female
Output ……………………………………………… CPR-137 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
10.4
–
5.7
–
2.5
–
–
–
Max.
6.6
5.0
1.8
–
11.9
15.0
6.4
320
3.2
470
18
1.5 : 1
Unit
V
A
A
s
kVdc
mAdc
kVdc
mAdc
kVdc
mAdc
dBm
–
Min.
–40
–50
Max.
+105
+85
Unit
˚C
˚C
ENVIRONMENTAL
Heat Sink Temperature ……………………………
Storage Temperature ………………………………
2
DATA SHEET ET0475EJ1V0DS00
LD7262 SERIES
TYPICAL OPERATION (Note 2, 3, 4 and 5)
Unit
Frequency ……………………………………………
6.15
GHz
Output Power ………………………………………
770
W
…………………………
6.3
V
Heater Current ………………………………………
Heater Voltage (Note 4)
1.5
A
Collector-1 Voltage …………………………………
6.2
kVdc
Collector-1 Current …………………………………
254
mAdc
Collector-2 Voltage …………………………………
2.9
kVdc
Collector-2 Current …………………………………
183
mAdc
Cathode Current ……………………………………
441
mAdc
Helix Voltage ………………………………………
11.3
kVdc
Helix Current ………………………………………
4.0
mAdc
Power Gain
at (SSG) ………………………
53.5
dB
at (LSG) ………………………
47
dB
Gain Variation
at 75 W ………………………
1.2
dB/600MHz
Gain Slope
at 75 W ………………………
0.012
dB/MHz
at 75 W ………………………
1.0
deg./dB
at 750 W ………………………
3.5
deg./dB
3rd Order Intermodulation ………………………
–31
dBc
AM-PM Conversion
(two equal carriers, 75 W total)
Spurious ……………………………………………
–60
dBc
Noise Figure …………………………………………
25
dB
Overall Efficiency …………………………………
35.6
%
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 ET0475EJ1V0DS00
3
LD7262 SERIES
LD7262 series OUTLINE (Unit in mm)
508 MAX.
384 ± 3.0
(104.65)
150 NOM.
86.8
12.7
139 NOM.
25.4 ± 0.2
55 NOM.
55.88 ± 0.2
24.6 ± 0.6
95.25 ± 0.2
139.7 ± 0.2
203.2 ± 0.2
266.7 ± 0.2
330.2 ± 0.2
393.7 ± 0.2
8- φ 10
COUNTER BORING
81.25 ± 1.0
96 MAX.
50.8 ± 0.2
45.35 ± 0.2
RF OUTPUT
CBR-137 FLANGE WITH
NO.10-32 UNF-2B THREADED HOLES
No.6-32 UNC-2B X 7.6 DP
NEAR AND FARSIDE
RF INPUT
TYPE SMA FEMALE
18- φ 4.2+0.4
–0
6 ± 0.5
38 NOM.
45.7 ± 0.2
45
55.5 MAX.
4
60 NOM.
LEAD COLOR
LEAD CONNECTIONS
LENGTH
BROWN
HEATER
500 mmMIN.
YELLOW
HEATER-CATHODE
500 mmMIN.
ORANGE
COLLECTOR-1
500 mmMIN.
BLUE
COLLECTOR-2
500 mmMIN.
GREEN
HELIX (GROUND)
500 mmMIN.
DATA SHEET ET0475EJ1V0DS00
LD7262 SERIES
DATA SHEET ET0475EJ1V0DS00
5
LD7262 SERIES
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appear in this document.
NEC Corporation does not assume any liability for infringement of patents, copyrights or other intellectual
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from use of such device. No license, either express, implied or otherwise, is granted under any patents,
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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
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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
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The quality grade of NEC devices is "Standard" unless otherwise specified in NEC's Data Sheets or Data
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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.