OPERATING INSTRUCTIONS
PRELIMINARY SET-UP
1. Connect the plug of the ac power cord to a117-
volt, 50/60 Hz ac power outlet.
2. To turn on the signal generator, set the MOD-
ULATION switch 15 to the CW position. The pilot
lamp 1should light.
3. Set the XTAL CALIBRATOR switch 13 to the OFF
position.
4. Set the RANGE switch 8to the desired frequen-
cy range.
5. Set the dial 5to the desired frequency with the
frequency control knob 6
6. Connect the rf output cable to the RF OUT
jack 11. The cable supplied with the signal gen-
erator is normally used. It contains abuilt-in
50-ohm termination. However, if the rf output
signal is to be applied directly to a50-ohm cir-
cuit, an unterminated rf cable should be used.
Such acable can be made from alength of 50-
ohm coaxial cable (RG-58A/U) terminated in a
microphone type female connector on one end
and the desired connector or terminations on
the other end.
7. Connect the rf output cable to the equipment
being tested. Connect the black lead to the
chassis first, then the red lead to the signal
injection point.
PRECAUTIONS
A. When performing stage-to-stage measure-
ments, always use adc blocking capacitor
between the red probe of the rf output cable
and the circuit into which the signal is in-
jected. This protects the attenuators of the
signal generator from possible damage by
the dc from the circuit under test. Trim the
capacitor leads as short as possible, while
still permitting adequate length for connec-
tions. The value of the blocking capacitor is
dependent upon the frequency of the rf out-
put signal. Suggested values are:
Ranges Aand B: .1 uF, 400 V
Ranges Cand D: .01 uF to .02 uF 400 V
Ranges E, H.>, Hi: 1000 pF
B. If the equipment into which the rf signal is
being injected uses an ac powered, trans-
formerless power supply, always use an iso-
lation transformer between the 117-volt out-
let and the equipment to prevent electrical
shock and possible damage to the equip-
ment. The equipment chassis becomes
grounded through the rf signal generator
when the rf cable is connected.
C. When connecting the rf output cable to
equipment under test, always cormect the
black lead to the equipment chassis first.
Otherwise, atransient voltage spike may oc-
cur when the connection is made that may
damage transistorized equipment.
D. Use a dc blocking capacitor in series with
the black lead of rf or 400-Hz output cables
if other than chassis reference is used in
equipment which has its chassis at earth
ground. The black terminal of the EXT MOD
jacks and the black probe of the rf cable ore
at eaith ground potential through the 3-wire
power plug. Serious damage to equipment
could result by using adirect connection.
SETTING THE SIGNAL LEVEL
1. Be sure the output is terminated in a50-ohm
load.
2. Set the MODULATION switch 15 to the CW po-
sition.
3. Set the METER switch 2to the CARRIER position.
4. Determine the amount of attenuation required
to produce the desired output level (refer to the
accompanying table). The desired output level
may be in millivolts, microvolts, or dB, but must
be converted to dB to correspond with the lab-
elling on the controls. In this unit 0dB =100
millivolts into a50-ohm load.
5. Place as many ATTENUATOR selectors 10 in
the IN position as required to come within 0to
f5dB of the desired total attenuation. All the
other ATTENUATOR selectors 10 must be in the
OUT position.
6. Set the FINE ATTENUATOR control 9for the
additional attenuation, as indicated on the meter
3(this should always be in the 0to —5dB re-
gion of the meter scale).
The total of all ATTENUATOR selectors and the
meter reading equals the total attenuation below
the 0dB (100 millivolt) reference level.
7. Higher levels of output are possible but seldom
required. Levels above -f 2dB must be meas-
ured with external equipment. At these higher
levels, the meter 3will peg, but no damage will
occur since the meter is protected against over-
load damage. For output levels above I- 2dB,
connect an rf voltmeter to measure the output
signal level and adjust the FINE ATTENUATOR
control 9for the desired signal level.
NOTES
A. For greater accuracy, use an unmodulated
signal level (MODULATION switch in CW
position).
B. If the output is not terminated in 50 ohms,
the output level is not calibrated. However,
the meter and ATTENUATOR selectors still
provide indication of relatively higher or
lower level.
C. For ranges H-j and H4,which provide har-
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