HP 3585A Service Manual page 74

Model 3585A
i. Press the 1 MO input impedance key on the 3585A.
j . Again check the amplitude of the scope waveform . It should be less than 0.07 V p-p .
This will confirm that the Return Loss of the Terminated input is greater than 1 4 dB .
k . Connect the equipment as shown in Figure 4-2. 750 Return Loss Test .
1 .
Press the 750 input impedance key on the 3585A.
m. Repeat Steps e thru i for the values in parenthesis .
n . Change the synthesizer frequency to 1 5 MHz.
o . Set the 3585A controls for MANUAL SWEEP 1 5 MHz .
p . Repeat Steps c thru m .
q . This completes the Return Loss Tests . Disconnect the test equipment .
h p 3 5 8 5 A
S P E C T R U M ANAL Y Z E R
1iI�
-' : : -'-' -' -' �-.l
m
e o e
S Y N T H E S I Z E R
Figure 4·2 . 7 50 Return Loss Test (Operational Verification)
j jjjj
0 ....J ....J ....J
...J ....J
-' � -.l -.l -.l-.l-.l-.l -'-'-'
Ej
-' � -.l -.l -.l-.l-.l-.l
-.l-.l-.l-.l -' -;-;
0
o 0 0 0 • •
LOAD POR T
SHORTED
15 OHM CABLE
15 OHM OUTPUT OR
50 OHM TO 15 OHM
M I N I _ LOSS PAD
OSC I L L OSCOPE
D
_
"
�" ,,
_
FEEDTHRU
TERM I NAT I ON
Performance Tests
4-1 5