APPLICATION NOTE
A wide-band class-A linear power amplifier (174 − 230 MHz) with two transistors BLV33
ECO7904
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APPLICATION NOTE
A wide-band class-A linear power amplifier (174 − 230 MHz) with two
transistors BLV33
ECO7904
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Philips Semiconductors
A wide-band class-A linear power amplifier (174 − 230 MHz) with two
transistors BLV33
CONTENTS 1 2 3 4 5 6 7 8 ABSTRACT INTRODUCTION DESIGN OF THE AMPLIFIER ADJUSTMENTS OF THE AMPLIFIER ASSEMBLING OF THE AMPLIFIER AND MECHANICAL DATA MEASURED RESULTS CONCLUSION REFERENCES
Application Note ECO7904
1998 Mar 23
2
Philips Semiconductors
A wide-band class-A linear power amplifier (174 − 230 MHz) with two
transistors BLV33
1 ABSTRACT
Application Note ECO7904
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 BLV33, coupled by means of 3 dB −90° hybrids. Each
transistor is adjusted in class-A at VCE = 25 V and IC = 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 dB. At this power level the cross-modulation varied from 6 to 7.5%. The power gain is between 8.35 and 8.6 dB. 2 INTRODUCTION
For application in T.V. transposers and transmitters for band III a wideband linear power amplifier has been designed with 2
transistors BLV33, coupled by means of 3 dB −90° hybrids. Each
transistor is adjusted in class-A at VCE = 25 V and IC = 3.25 A. 3 DESIGN OF THE AMPLIFIER
For class-A operati...