DATA SHEET

Document No. ET0215EJ3V0DS00 (3rd edition)

Date Published August 1998 M

Printed in Japan

30 GHz, 150 W CW, CONDUCTION COOLING, HIGH POWER GAIN

HIGH POWER TRAVELING WAVE TUBE

FOR COMMUNICATIONS

LD7235 SERIES

The information in this document is subject to change without notice.

©

1996

For safe use of microwave tubes, refer to NEC document “Safety instructions to all personnel

handling electron tubes” (ET0048EJ

∗V∗UM00)

GENERAL DESCRIPTION

The NEC LD7235 series of PPM-focused traveling wave tubes are designed for use as final amplifiers in the

earth-to-satellite communications transmitter, LMDS (Local Multipoint Distribution Service) and other advanced

communication systems.

Three models of the LD7235 series are capable of delivering an output power of 150 W over the range of

26.5 GHz to 31.1 GHz and provide a high power gain of 50 dB at 150 W output power. These are equipped with

dual-stage depressed collector for enhancing overall efficiency and a single collector.

Furthermore, they are of rugged and reliable design offering long-life service.

FEATURES

™ High Power Gain

The power gain is typically 50 dB at 150 W level.

™ Simple Cooling System

The tubes are conduction-cooled, so that the cooling systems are greatly simplified.

™ PPM Focusing

The tubes are PPM (Periodic Permanent Magnet) -focused, eliminating entirely the focusing power supplies

and interlock circuits.

™ Rugged Construction

The tubes are designed to be rugged, therefore they are suitable for transportable systems.

™ Long Life and High Stability

The tubes employ an advanced impregnated cathode with a low operating temperature for long life.

™ 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.