User Manual
Table Of Contents
- 1GENERAL
- 1.1Introduction
- 1.2Performance Specification
- 2THEORY OF OPERATION
- 2.1Amplifier Operation
- 2.2Power Requirements
- 2.3RF Circuitry
- 2.3.1VT-3/150 Lowpass Filter
- 2.4Power Control Circuitry
- 2.5Power Sensing Circuitry
- 2.5.1Output Power Sense
- 2.5.2VSWR Sense
- 2.5.3VSWR Overload
- 3VT-3/150 AMPLIFIER ALIGNMENT
- 3.1General
- 3.2Repair Note
- 3.3Recommended Test Equipment List
- 3.4Printed Circuitboard Numbering Convention
- 3.5Standard Factory Settings and Jumper Configuration
- 3.6VT-3/150 AmplifierAlignment
- 3.6.1General
- 3.6.2VT-3/150 Amplifier Adjustment
- 3.6.2.1General Set-Up
- 3.6.2.2Output Power Alarm (Forward Power)
- 3.6.2.3Output Power
- 3.6.2.4Antenna VSWR Alarm (Reverse Power)
- 3.6.2.5Antenna VSWR Overload
- 3.6.2.6Procedure Verification
- 4ILLUSTRATIONS AND SCHEMATIC DIAGRAMS
- 4.1VT-3/150 VHF Amplifier Component Layout
- 4.2VT-3/150 VHF Amplifier Schematic Diagram
- 4.3VT-3/150 VHF Lowpass Filter Component Layout
- 4.4VT-3/150 VHF Lowpass Filter Schematic Diagram
- 5PARTS LISTS
- 5.1VT-3/150 Amplifier Electrical Parts List
- 5.2VT-3/150 Low Pass Filter Electrical Parts List
- 5.3VT-3/150 Amplifier Mechanical Parts List
- 6REVISION HISTORY
DE
DANIELS
ELECTRONICS
3-2
VHF Amplifier Instruction Manual VT-3 132 - 174 MHz
2
It is
recommended
that the radio
communications
test set be frequency locked to an
external
reference
(WWVH,
GPS,
Loran C) so that the high
stability
oscillator
may be
accurately
set to
within its ±1 ppm frequency tolerance.
3.4
Printed Circuitboard Numbering Convention
To ease
troubleshooting
and
maintenance
procedures,
Daniels
Electronics
Limited
has adopted a
printed
circuitboard
(PCB) numbering
convention
in which the last two digits of the
circuitboard
number represent the
circuitboard
version. For
example:
• PCB number 43-9120
10
indicates
circuitboard
version 1.0;
• PCB number 50002-
02
indicates
circuitboard
version
2.0.
All
PCB's
manufactured
by
Daniels
Electronics
are
identified
by one of the above conventions.
3.5
Standard Factory Settings and Jumper Configuration
The
VT-3/150
Amplifier
is factory configured as follows:
• Open
collector
configuration
for
Output
Power Alarm.
• Open
collector
configuration
for
Antenna
VSWR Alarm.
The corresponding jumper settings are:
• Jumper JU1: not
installed
Output
power
alarm
-
linear
output
• Jumper JU2:
installed
Output
power
alarm
- open
collector
output
• Jumper JU3:
installed
Antenna
VSWR
alarm
- open
collector
output
• Jumper JU4: not
installed
Antenna
VSWR
alarm
-
linear
output
3.6 VT-3/150 Amplifier
Alignment
3.6.1 G
eneral
The
VT-3/150
Amplifier
is a frequency
sensitive
module that is factory assembled to
operate
in one
of two frequency bands: 132 to 150 MHz or 150 to 174 MHz. The
amplifier
requires 7 dBm of
input power and is
continuously
adjustable
over the its power range of 2.0 to 8.0 Watts. The
VT-3/150
Amplifier
provides
Output
Power and
Antenna
VSWR
Alarm
outputs which can be
configured for open
collector
output or
linear
operation. The amplifier's output power
level
and
alarm
levels can be set without
detaching
the
amplifier
from the
transmitter
board.
However,
to
change the
configuration
of the output power
alarm
or the
Antenna
VSWR alarm, the VT-3/150
Amplifier
must be
detached
from the MT-3
Transmitter
Board. Refer to page 4-2
"VT-3/150
VHF
Amplifier
Component
Layout" for the
location
of solder jumpers JU1 to
JU4.