Nautel NV15, Руководство по эксплуатации и обслуживанию

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NV15/NV20 Operations and Maintenance Manual Description
Page 1-6 Issue 3.2 2013-10-01
RF power stage
See Figures
SD-7
,
SD-8
and
SD-9
. The RF power stage accepts the intermediate RF drive inputs from
the RF drive stage and generates the final RF output. It consists of two RF power modules, a module
backplane PWB (A17), a combiner/filter (A16), an output power probe (A13), a 2-input reject load
assembly (A14) and a reject load interface PWB (A15).
RF power module
See Figure
SD-7
(see the NV15/NV20 Troubleshooting Manual for a detailed RF power module
description) and “RF Power Module Block Diagram” on page 1-11 .
Each of the two RF power modules provides up to 2750 W (for NV5) or 2062.5 W (for NV3.5) of
RF output power and is comprised of an IPA power amplifier PWB, eight power amplifier PWBs,
power module interface PWB, combiner PWB, splitter PWB and six cooling fans. The intermediate
RF drive outputs from the RF drive stage are applied to the RF power modules via module backplane
PWB 1-4 (A17). Within each RF power module, the intermediate RF drive signal is sampled and then
drives the IPA amplifier. The IPA output is sampled then split to drive the module's eight PAs. The
IPA Volts and PA Volts inputs from the associated switching power supply modules control the RF
output of the IPA and eight PAs, respectively. The RF power module receives alarm and status signals
(
PS Temp , PS Fail , PS AC Fail , and PS Module Present ) from the ac-dc power stage. The RF power
module also provides a Pwr Supply Inhibit signal (one for each of the power module’s dual supplies) to
the ac-dc power stage, which, when active, inhibits the associated switching power supply. A PA V
Sample and IPA V sample from each RF power module is applied to the control/monitor stage. The
control/monitor stage supplies a PA Volts Inhibit signal, which controls the PA outputs of the RF
power module.
Module backplane PWB
See Figure
SD-7
. The two RF power modules have an associated module backplane PWB which
interfaces with all module inputs and outputs, except for the RF output. It also provides the fan volts
connections for the module's cooling fans. The setting of dipswitches S1 through S4 assign a four-bit
address for each specific module based on module position. Jumper E1 is set to
TERM
on RF power
module 2 (the last module) to terminate the RS-485 serial communication cable.
Combiner/filter
See Figure
SD-8
.