Wavetek 3000 Instruction Manual page 209

INTRODUCTION
This option provides a constant ampli-
tude Auxiliary RF Output signal on the
rear panel of the signal genera-
tor . The
amplitude (-10 dBm) of
this
signal is sufficient to drive most fre-
quency counters . This auxiliary signal
does not contain amplitude modulation,
however, it does contain frequency
modulation .
This
factory-installed option entails
changing the M9W Oscillator to an M9W-1,
the addition of an M37 Amplifier module,
harnessing, and additional cabling to
the rear panel . The addition and oper-
ation of this option has no effect on
the operation or
specifications of the
signal generator . See Figure 5-6 for
location of the M37 and cable connections .
SPECIFICATIONS
Frequency Range
1 to 520 MHz
Level
-10 dBm ± .5dB
(70 mV)
Harmonic output
25 dB below fun
damental from 1
to 520 MHz .
OPERATING INSTRUCTIONS
To use
the Auxiliary RF Output,
dis-
connect the 500 termination on ttie rear
panel and connect a frequency
counter
or other monitoring device with a 5052
coaxial cable . The Auxiliary RF Output
cable should be kept as short as possi-
ble . The output is controlled by a rear-
panel on/off switch .
IMPORTANT
When not in fuse, terminate the
Auxiliary RF
Output with the
50 52 terminator supplied .
Note :
Although the reverse isolation
of the Auxiliary RF Output is
approxi-
mately 30 dB, a signal that is coupled
into the Auxiliary
RF Output could be
coupled to the main RF output on the in-
strument's front panel . For example,
subharmonic signals at a counter's input
can be
coupled through the instrument
and applied to the device under test .
CIRCUIT DESCRIPTION
OPTION -4
AUXILIARY RF OUTPUT
The
M37 module contains a wide band
amplifier, monitor diode, an error ampli-
fier and a voltage variable attenuator .
The input
signal to the M37 module is
fed thru the VVA to amplifier IC1 .
The
approximate gain of the amplifier is
13 dB from 1 to 520 MHz . The monitor
diode, CR2, detects the output from the
wide
band amplifier . This detected
level is compared to a DC reference by
the error amp, IC2 . The output of the
error amp is fed to the PIN diode (VVA)
attenuator which changes the input level
to the
wide band amplifier until the
monitored signal produces a DC level
equal to the reference level . This ref-
erence level is adjusted by R5,
the
output level control .
The output impedance is provided by the
resistor,R2,connected between the moni-
tor and the RF output connector .
MAINTENANCE
The only
maintenance for the Auxiliary
RF Output is a
periodic check of the
output level .
If a malfunction occurs,
a trouble can be localized and repaired
with the aid of the theory of operation
and the schematics .
The M37 Schematic
is included in this section. The M9W/
M9W-1 Schematic is located in Section 7
of this manual .
8/4- 1