Giga-tronics GT 9000, Руководство по эксплуатации и техническому обслуживанию

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3
Theory of Operation
3.1 Introduction
This chapter contains the theory of operation of the assemblies in the GT 9000 Microwave
Synthesizer. The General Circuit Theory in Section 3.2 describes the circuit operation on a
block diagram level. The Assembly Circuit Descriptions in Section 3.3 are at component level.
3.2 General Circuit Theory
The interior of the GT 9000 is divided into five main sections as illustrated in the top-view
diagram in Figure 3-1.
•
The PC assemblies in the I/O bus control the frequency of the RF output, including YIG
driver circuits and phase lock loop circuits.
•
The PC assemblies in the CPU bus make up the internal computer and peripheral circuits to
control the level and modulation of the RF output.
•
The microwave deck houses the microwave-frequency devices. The YIG oscillators are
mounted on the underside of the microwave deck. In instruments which include the
downconverter range (below 2 GHz), a downconverter module is mounted on top of the RF
module.
•
The power supply furnishes DC voltages to the various circuits. It is contained in a metal
housing behind the front panel.
•
The AC power input and fuse are located in the space between the CPU bus and the rear
panel. The instrument timebase is also located there.
Figure 3-1. Internal Chassis Layout
Manual No. 120AM00250, Rev C, September 1998
3-1