HP 8901B Operation And Calibration Manual page 236

Model
8901B
Operation
Tuning
Mode
Automatic
LO Frequency
Down Selected Approximate
Conversion
IF LO Frequency
Yes
1 . 5 MHz
Input
+
IF
Yes
455 kHz
Input
+
IF
No
1 . 5 MHz 101.5 MHz
FUNCTIONS
Special Function 33
(LO
Frequency)
Manual
DESCRIPTION
Special finction 33.0 enables the Modulation Analyzer to display the local oscillator
(LO)
frequency.
Yes
1 . 5 MHz
Keyed In
+
IF
Yes
455 kHz
Keyed In
+
IF
No
1 . 5 MHz 101.5 MHz
PROCEDURE
To measure the
LO
frequency, key in 33.0
SPCL.
>
%-
MEASUREMENT TECHNIQUE
-
$+
The LO frequency is essentially measured directly by the counter. The frequency that the
LO
is tuned
to
depends on (1) whether automatic tuning or manual tuning is being used,
(2)
whether the RF input
signal is being down-converted, and (3)
which
IF is
being used. The following table summarizes
LO
tuning. (Refer to
R F
Requency Z h i n g on page 3-115 for more information.)
BLOCK DIAGRAM
I
LO
frequency
Measurement Block Diagram
LO Frequency
3-127