M10W - Output Amplifier - Wavetek 3000 Instruction Manual

THEORY OF OPERATION
IX-ROM
//134
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Figure 3-12 . M9W
The main function of the M10W module is
to amplify the RF signal from the
M9W
to a level programmable between -7 and
+13 dBm.
A leveler circuit maintains a
constant
amplitude output signal over
the wide frequency range . The Unleveled
light driver causes the
front panel
light to glow when
the leveler circuit
exceeds its proper
operating range .
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1199 MHz
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3 .8
M10W-6 - OUTPUT AMPLIFIER 3 .8 .2
Sweep Oscillator
Leveler
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The leveler uses a peak detector,
dif-
ferential amplifier and a PIN
diode
attenuator . The peak
detector is fed
from the RF output .
The resulting level
is compared to a DC (or AM) reference by
the differential amp which supplies the
control current to the PIN diode atten-
uator .
If the detector RF output de-
viates from the
reference level, the
See Figure 3-13 .
3 .8 .1 Amplifier
signal to the PIN diode causes the
to be decreased or increased .
In addition to providing a flat
input
frequency
This section is a four-transistor wide response,
the leveler allows for elec-
band
amplifier which can increase the
tronic control of the RF output ampli-
RF by about 23 dB .
tude by varying the DC reference . The
reference comes from the meter
board
(C315) .