Transmitter Flatness At -40 Dbm - HP 4935A Operating And Service Manual

Model 49:GA
PERFORMANCE TESTS

Transmitter Flatness at -40 dBm

4-14.
M O D E L 4 9 3 5 A
VOLTMETER
0
AC CALIBRATOR
Figure 4-2. Transmitter Flatness Test at -40 dBm
2 banana plug test cables
Output Power Supply Multimeter
ON
. . . . . . . . . . . . .
N O R press In
S E T IJl' . press in TRMT 60011
HRG out
out
both HOI,I)s out
N O I S E
(1004 Hz)
Adjust the l'ower Supply to provide
2 .
to exactly -40 dRm as follows.
the A(: Calibrator to 7.746 m V (-40 dRm into 600 ohms) at 1004 Hz with the output
floating.
AC (:alibrator to the t20
TRMT 310 jack. Monitor the +20 amplifier
output with the voltmeter.
Adjust th(l 49:GA control until the voltmeter reading is the same as the
output voltage in step b. The AC Calibrator and the 49XA are both set to
A 600 ohm termination is provided by the amplifier in the IXagnostic
Service Kit and must be added if a high impedance amplifier is used.
3-4