Design of tube power amplifiers for optimum FM transmitter performance

Author

Shrestha, Mukunda B.

Author_Institution

Broadcast Electron. Inc., Quincy, IL, USA

Volume

36

Issue

1

fYear

1990

fDate

3/1/1990 12:00:00 AM

Firstpage

46

Lastpage

64

Abstract

Tube amplifiers are extensively used in modern high-power FM broadcast transmitters. The power amplifier bandwidth affects not only the modulation performance, but also the transmitter´s immunity to RF intermodulation. The tradeoffs involved and the choice of bandwidth are discussed. The design of tube power amplifiers for optimum FM performance requires careful considerations in the selection of input-matching and output-coupling circuit topologies, due to their effects on the transmitter amplitude and group delay responses. Results of computer circuit analysis and of measured amplitude and group delay responses are compared for different circuit topologies. Modulation performance data of a typical 20 kW FM transmitter are also presented to illustrate the effects of tube power amplifier input and output circuits

Keywords

circuit analysis computing; electron tubes; frequency modulation; power amplifiers; radio transmitters; radiofrequency amplifiers; 20 kW; RF intermodulation; amplitude response; bandwidth; computer circuit analysis; design; group delay responses; high-power FM broadcast transmitters; input matching circuit; modulation performance; output-coupling circuit topologies; tube power amplifiers; Bandwidth; Broadcasting; Circuit analysis computing; Circuit topology; Delay effects; High power amplifiers; Power amplifiers; Radio frequency; Radiofrequency amplifiers; Transmitters;

fLanguage

English

Journal_Title

Broadcasting, IEEE Transactions on

Publisher

ieee

ISSN

0018-9316

Type

jour

DOI

10.1109/11.52364

Filename

52364