DATA SHEET
Document No. ET0404EJ2V0DS00 (2nd edition)
(GC-1069)
Date Published August 1998 M
Printed in Japan
17 GHz BAND, 1.7 kW, HIGH EFICIENCY, HIGH POWER GAIN
The information in this document is subject to change without notice.
©
1994
HIGH POWER KLYSTRON
FOR GROUND TERMINALS
LD7111 SERIES
For safe use of microwave tubes, refer to NEC document “Safety instructions to all personnel
handling electron tubes” (ET0048EJ∗V∗UM00)
GENERAL DESCRIPTION
The series of NEC LD7111 is a five-cavity Klystron Amplifier
and ideal for use in the earth-to-satellite communication sys-
tems. These are designed for operating at 1.7 kW CW over the
frequency range of 17.3 to 18.4 GHz.
The instantaneous bandwidth of minus one-decibel is at least
90 MHz over the entire 1.1 GHz range.
All tubes are forced-air-cooled at any power level. An auto-
matic channel tuner , which changes the operating frequency very
quickly and simply, is available in all the series.
Furthermore, they are of rugged and reliable design offering
long life service.
NEC LD7111 series is compatible with VKU7791Z6 by using
an additional adapter.
FEATURES
™Compact and Light Weight (27 kg approx.)
™High Efficiency
(The DC to RF conversion efficiency is typically 23 % or
higher.)
™High Power Gain
™Long Life and High Stability
™Simple Cooling System (forced-air-cooled)
™Automatic Channel Tuner (8-12 Channels)
Hand Tuner model is also available.
™Permanent Magnet Focusing
™Rugged Construction
2
LD7111 SERIES
GENERAL CHARACTERISTICS
ELECTRICAL
Frequency ……………………………………………… 17.3 to 18.4 GHz
Output Power ………………………………………… 1.7 kW
Heater Voltage ………………………………………… 6.5 V
Heater Current ………………………………………… 3.2 A
Cathode Type ………………………………………… Indirectly Heated, Impregnated
Cathode War m-up Time …………………………… 300 s
MECHANICAL
Dimensions …………………………………………… See Outline
Weight ………………………………………………… 27 kg approx.
Focusing ……………………………………………… Permanent Magnet
Mounting Position …………………………………… Vertical (Cathode down)
Cooling ………………………………………………… Forced Air
Electrical Connections ……………………………… See Outline
RF Connections
Input ………………………………………………… Mates with UG-419/U Flange
Output ……………………………………………… Mates with UG-419/U Flange
Cavity Tuning Method ……………………………… 8-12 Channel Preset Tuning
(Hand Tuner is also available)
ABSOLUTE RATINGS ( Note 1, 2 and 3 )
ELECTRICAL Min. Max. Unit
Heater Voltage ………………………………………… 4.5 7.8 V
Heater Surge Current ……………………………… – 7.0 A
Heater Current ………………………………………… – 4.5 A
Heater Warm-up Time ……………………………… 300 – s
Body Voltage ………………………………………… – 10.0 kV
Body Current ………………………………………… – 25.0 mA
Collector Voltage……………………………………… – 10.0 kV
Collector Current……………………………………… – 1.0 A
Cathode Current ……………………………………… – 1.0 A
DC Input Power ……………………………………… – 9.3 kW
Load VSWR
Normal Value ……………………………………… – 1.2 : 1
Instantaneous Value ……………………………… – 1.5 : 1
MECHANICAL
Collector Temperature ……………………………… – +250 °C
Cooling Air Temperature …………………………… –10 +50 °C
Collector Air Flow …………………………………… 515 – kg/hr
Body Air Flow ………………………………………… 83 – kg/hr
Gun Air Flow ………………………………………… 41 – kg/hr
ENVIRONMENTAL
Ambient Temperature
Operating …………………………………………… +5 +50 °C
Storage ……………………………………………… –50 +70 °C
3
LD7111 SERIES
TYPICAL OPERATION (Note 3, 4 and 5)
Unit
Frequency ………………………………………………… 17.7 GHz
Heater Voltage (Note 4) ………………………………… 6.5 V
Heater Current …………………………………………… 3.2 A
Body Voltage……………………………………………… 9.4 kV
Body Current……………………………………………… 3.0 mA
Collector Voltage ………………………………………… 9.4 kV
Collector Current ………………………………………… 0.85 A
Cathode Current ………………………………………… 0.85 A
DC Input Power ………………………………………… 8.0 kW
Driving Power …………………………………………… 100 mW
Output Power …………………………………………… 1.8 kW
Power Gain ……………………………………………… 42 dB
Band Width (-1 dB) ……………………………………… 90 MHz
Collector Air Flow ……………………………………… 530 kg/hr
Collector Air Pressure Drop …………………………… 2,000 Pa
Body Air Flow …………………………………………… 85 kg/hr
Body Air Pressure Drop ………………………………… 34 Pa
Gun Air Flow……………………………………………… 43 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. Equipment design should limit voltage and environmental variations so that ratings will be
exceeded.
Note 2 : The Klystron body should be at ground potential in operation.
Note 3 : All voltages are referred to the cathode potential except the heater voltage.
Note 4 : The optimum operating value is shown on a test performance sheet for each tube.
Note 5 : Characteristics and operating values on this Data Sheet are based on performance test. These values
may be changed as a result of additional information or product improvement. NEC should be con-
sulted before using this information for equipment design. This data sheet should not be referred to a
contractual specification.
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.
LD7111 SERIES
LD7111 SERIES OUTLINE (Unit in mm)
5.8 ± 0.1
234.7 ± 0.5
(260)
(208)
252.5 ± 0.25
(275)
(125)
(10)
(128)
(208)
(177.8)
139.7 ± 0.25
142.2 ± 0.5
133.4 ± 0.25
106 ± 3 33 ± 1.5
(180)
(147)
A
B
Detail B
6.3
φ
+0.01
–0.05
5.8±0.1
View from A
Electrode
Heater
Heater-Cathode
Color of Lead
Yellow
White
115 ± 1
Lock / Unlock Shaft
4-No.4-40 UNC
depth 5.8 MAX.
Body Col & Thermostat
Terminal Thermostat
(Nomally Close)
RF Output
UG-419 / U
RF Input
UG-419 / U
Channel Shaft
36.84 ± 0.3 36.84 ± 0.3
17.5 ± 0.315.5 ± 0.3
190 ± 2
148 ± 2
390 MAX.
(111)(224)
(201)
26.15 ± 0.3 27 ± 0.3
(136)
(6.5) (7)
(8)
(14.65) (13.4)
(335)
φ
( 38)
φ
4- 5.6
φ
( 70)
φ
5- 5
φ
