HP 8591C User Manual page 103

Channel Measurements
Making Channel Measurements
View ingress test
1. Select a channel, then press VIEW INGRESS A marker is placed on the
2. After the displayed modulation and noise are reduced with minimum hold,
3. During the test, you can change the default 100 kHz resolution bandwidth
4. Demodulate the ingress signal in AM or FM by pressing the
5. Press VIEW CD-CHNL to set the analyzer to see co-channel interference.
2 - 6 0
peak of the carrier, and the delta marker is activated.
use the knob to position the delta marker on a signal appearing above the
noise. The frequency and amplitude differences between the peak carrier
level and the marker appear in the active function block. See Figure 2-40.
36.8
C E N T E R 1 7 7 . 0 0 0 M H z
Y R E S BW 1 0 0 kHr
(RBW). For example, you might select 30 kHz RES BW to improve
resolution of signals close to the visual carrier. Return to 100 kHz RBW by
selecting 100 kHz RES BW
Selecting either resolution bandwidth resets the minimum hold function
used in the test to improve viewing of ingress.
LISTEN AT MKR then DEMOD AM FM Press LISTEN OFF to return to
the previous menu.
Also, see Chapter 5 for more information about
See Figure 2-41.
VIEW CO-CHNL
M K R a 3 . 0 0 0 FiHz
AT
:
S P A N 6 . 0 0 8 IlHz
1 kHz
Figure 2-40. View Ingress
- 6 0 . 3 9 dB
V I E W
C O - C H N L
L I S T E N
A T M K R
R E S BW
3 0
R E S 3W
MENU
RT