TM 11-5820-801-30
CHAPTER 2
FUNCTIONING OF EQUIPMENT
Section I. INTRODUCTION AND SIGNAL AMPLIFICATION
parametric amplifier stages. A power supply (1PS1)
2-1. Introduction
supplies the operating dc voltages. Monitors provide
a. Amplifier, Parametric AM-6602/MSC-46(V) is a
visual information on the dc voltages (VOLTAGE meter
two-stage RF preamplifier. The first stage is operated at
1M4), the relative pump power (PUMP meter 1M5) and
a cryogenic temperature (about 18K). The temperature
operating time (PARAMP ELAPSED TIME meter 1M3).
is obtained by the use of Helium Refrigerator, Unit 4.
Test points (FIRST STAGE and SECOND STAGE
Unit 4 is government supplied under another contract;
VARACTOR VOLTAGE TEST) provide convenient
therefore, the functioning and maintenance of Unit 4 is
methods of sampling varactor bias voltages on Unit 1.
not described in this manual.
b. Functionally Amplifier, Parametric AM-6602/-
2-3. Vacuum Vessel Module 2A3 (First Stage
MSC-46(V) can be divided into three parts: signal
Amplifier)
amplification, internal temperature control, and switching.
a. General. Vacuum Vessel Module 2A3 (first stage
Monitoring circuits with visual indicators are subcircuits in
amplifier) consists of a ferrite paramp circulator (5 port, 3
each of the functional circuits. Visual monitors include
meters, panel and fuse lamps, and a temperature gage.
and a bandpass pump filter through which the pump
The primary monitors are located on Local
power (from 2A1) enters the paramp varactor (fig. 2-1).
Control/Monitor Assembly, Unit 1, front panel (fig. 2-4)
To minimize resistive noise generation, the first stage
and on Remote Control/Monitor Assembly, 3A1, front
components (paramp circulator, paramp varactor and
panel (fig. 3-4). There are, in addition, three panel
pump filter) are operated at an ambient temperature of
lamps, four fuse lamps, and a temperature gage on
about 18K, cooled by means of Refrigerator Unit
module panels in Frame Assembly, Unit 2 (fig. 3-14).
Assembly 4A3, part of Unit 4. The first stage amplifier
typically operates at a center frequency of 7.5 GHz, has
2-2. Block Diagram of Signal Amplification Circuit
a bandwidth of 0.50 GHz and produces a net gain of 15.2
dB.
circuit. The circuit consists of two parametric amplifier
stages (2A3 and 2A2) interconnected by band-pass filter
2A4. A klystron pump source (2A1) supplies both
2-1
