C315 - Meter Board - Wavetek 3000 Instruction Manual

THEORY OF OPERATION
3 .2 .3 Subassembly Descriptions
The overall block diagram discussed in
this section describes basically how the
instrument functions as a unit . The
unit is made up of ten module assemblies
and three printed circuit
card assem-
blies .
These can be identified in Fig
ure 5-6 . Sections 3 .3 thru 3 .15 de-
scribe the operation of each subassem-
bly . The name of the subassembly_ de-
scribes, to an extent, the primary func-
tion it performs .
3 .3 C315 - METER BOARD
The primary function of this assembly
is to provide the program voltage to
the leveler circuit for the RF amplifier .
It also includes the RF output level
3 .3 .1
Level Program
Figure 3-8 . C315 - Meter Board
meter which appears through the instru-
ment front panel . See Figure 3-8 .
During CW
operation of the instrument,
the level program
is controlled by the
VERNIER on the front panel .
The output
of this control goes to two range cali-
bration circuits, "High" and "Low" . The
range calibration circuits convert the
voltage from the VERNIER to a voltage
level appropriate to drive the leveler
circuit in the M10W .
The "Low" circuit provides the program
for all ranges of the detented power
output dial except +10 dBm . At "+10"
the level program is taken from the
"High" circuit . The "High" level program
enables the full gain capabilities of the
M10W to be used when the output is not
amplitude modulated .
LEVEL PF'Oc' 5=f%trl
TG
/N/UW