DATA S H E E T
Document No. ET0190EJ3V1DS00 (3rd edition)
Date Published August 1998 M
Printed in Japan
6 GHz, 600 W/700 W CW, PPM FOCUSING,
HIGH POWER GAIN
The information in this document is subject to change without notice.
1996
HIGH POWER TRAVELING WAVE TUBE
FOR GROUND TERMINALS
LD7217 SERIES
For safe use of microwave tubes, refer to NEC document "Safety instructions to all personnel
handling electron tubes" (ET0048EJ
V
UM00)
GENERAL DESCRIPTION
NEC LD7217 series of PPM-focused traveling wave tubes are designed for use as final amplifiers in the earth-to-
satellite communications transmitter.
LD7217S and LD7217 are capable of delivering an output power of 600 W and 700 W over the range of 5.85 to
6.425 GHz and provide a high gain of 45 / 54 dB at 600 / 700 W level . In addition, LD7217W is capable of delivering
an output power of 700 W with a gain of 54 dB over the range of 5.85 to 6.65 GHz. The LD7217 series provide a flat
gain variation of 1.5dB (LD7217S) ,1.0dB (LD7217) and 1.8dB (LD7217W) at any power level.
Furthermore, these are of rugged and reliable design offering long-life service.
LD7217S is fully compatible with VTC6361B3, and LD7217 is also fully compatible with VTC6361B4.
FEATURES
TM High Power Gain
The power gain is typically 45 dB at 600 W level and 54 dB at 700 W level.
TM Simple Cooling System
All the tubes are forced-air-cooled, so that the cooling systems are greatly simplified.
TM PPM Focusing
The tubes are PPM (Periodic Permanent Magnet) -focused, eliminating entirely the focusing power supplies and
interlock circuits.
TM Rugged Construction
The tubes are designed to be rugged, therefore they are suitable for transportable systems.
TM Long Life and High Stability
The tubes employ an advanced impregnated cathode with a low operating temperature for long life.
TM Microdischarge Free
The tubes are carefully designed to be free from microdischarge in the electron gun for long term operation,
therefore they are suitable for digital communication service.
2
LD7217 SERIES
GENERAL CHARACTERISTICS
ELECTRICAL
Frequency
LD7217, LD7217S ....................................
5.85 to 6.425 GHz
LD7217W ................................................
5.85 to 6.65 GHz
Output Power
LD7217S ................................................
600 W
LD7217, LD7217W ....................................
700 W
Heater Voltage .............................................
6.3 V
Heater Current .............................................
1.7 A
Type of Cathode ..........................................
Indirectly heated, Impregnated
Cathode Warm-up Time
..............................
180 s
MECHANICAL
Dimensions ................................................
See Outline
Weight ......................................................
7 kg approx.
Focusing
...................................................
Periodic Permanent Magnet
Mounting Position .......................................
Any
Electrical Connections .................................
AMP LGH-1I
Thermal Switch Connection
........................
Deutsch DM9601-3P
RF Connections
Input ......................................................
N-Female
Output ...................................................
Mates with CPR-137F Flange
Cooling ......................................................
Forced Air
ABSOLUTE RATINGS (Note 1, 2 and 3)
ELECTRICAL
Min.
Max.
Unit
Heater Voltage ................................................ 6.0
6.6
V
Heater Surge Current
....................................
5.0
A
Heater Current ................................................ 1.5
2.5
A
Heater Warm-up Time .................................... 180
s
Helix Voltage
................................................ 10.2
11.9
kV
Helix Current
................................................
25
mA
Accelerating Anode Voltage
........................... 0
Note 5
kV
Accelerating Anode Current
...........................
2.0
mA
Collector Voltage ............................................. 5.7
7.5
kV
Cathode Current .............................................
475
mA
Drive Power ...................................................
0.1
W
Load VSWR ...................................................
1.7:1
MECHANICAL
Min.
Max.
Unit
Cooling Air Flow ............................................. 204
kg/hr
Ambient Temperature
Storage ...................................................... 30
+70
C
Operation ................................................... 10
+60
C
3
LD7217 SERIES
TYPICAL OPERATION (Note 2, 3 and 6)
LD7217S
LD7217, LD7217W
Unit
Frequency ...................................................
5.85 to 6.425
5.85 to 6.425, 5.85 to 6.65
GHz
Output Power .............................................
600
700
W
Heater Voltage (Note 4) .................................
6.3
6.3
V
Heater Current .............................................
1.7
1.7
A
Helix Voltage ................................................
11.0
11.2
kV
Helix Current ................................................
6.0
3.0
mA
Anode Voltage .............................................
11.0
11.2
kV
Anode Current .............................................
0.3
0.1
mA
Collector Voltage ..........................................
6.0
6.2
kV
Cathode Current ..........................................
425
430
mA
Power Gain
................................................
48 (at 60 W)
57 (at 70 W)
dB
45 (at 600 W)
54 (at 700 W)
dB
Gain Variation .............................................
1.5
1.0 (LD7217)
dB/ 575 MHz
1.8 (LD7217 W)
dB/800 MHz
Gain Slope ...................................................
0.01 (at 60 W)
0.015 (at 70 W)
dB/MHz
AM-PM Conversion .......................................
1.5 (at 60 W)
1.5 (at 70 W)
deg./dB
3.5 (at 600 W)
3.5 (at 700 W)
deg./dB
3rd Order Intermodulation
(two equal carriers, 350 W total) .....................
19
19
dBc
Air Flow ......................................................
204
204
kg/hr
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 : The accelerating anode voltage should be at cathode potential for the off condition, and at helix for the
full cathode current condition. The accelerating voltage should not exceed the helix voltage by 250
volts.
Note 6 : 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.
LD7217 SERIES
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, copy-
rights or other intellectual property rights of NEC Corporation or others.
LD7217 SERIES OUTLINE (Unit in mm)
11.9
6.4
0.5
127
1
117
0.5
107
2
98.5
1
106.5
1.5
139.7 Max.
87.4
0.5
50.8
0.5
18.3
0.5
152.4
0.5
127
76.2
0.5
165.1
1.5
139
1.5
76.2
122
81.3
0.5
19
0.5
200
1
19
1
101.6
0.5
1
01.6
0.5
1
01.6
0.5
546.1 Max.
203.2
0.5
455.7
11
9
0.5
16.5
2.5
247
2.5
175
2.5
129.5
4
342.9
31.8
0.5
Air Inlet Interface
Air Outlet
No. 6-32 UNC-2B Threaded Holes
8 Plcs
AMP LGH
-1I
Connector
10 Captive Fixing Screws
No. 8-32 UNC-2A
Thermal Switch Connector
Deutsch DM9601-3P
1 & 2-Thermal Switch
3-Ground. (Helix)
Contacts N.C.
No. 6-32 UNC-2B
Threaded Holes
8 Plcs
RF Input
Type N Female
RF Output
CPR-137F Flange
(No. 10-32 UNF-2B
Threaded Holes)
Air Inlet
(Side Optional)
Anode
Heater
Collector
Heater-Cathod
e
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