Agilent Technologies HP8648A Weather Radio User Manual


 
AM Transmitters
129
Measurement Procedure:
1. Connect the Transmitter as shown.
CAUTION: The RF present at the Test Set RF IN/OUT connector must not exceed 60W
continuous (or 100 Watts for 10 sec/minute) or permanent instrument damage
may result.
On the Test Set:
2. Press the PRESET key.
3. Press the TX key.
Using the knob and data entry keys:
4. Set AF Anl In to AM Demod.
5. Set Filter 1 to 300 Hz HPF.
6. Select the AF Freq Meter.
7. Select Distn from the Choices field.
8. Set AFGen1 Lvl so that displayed AM depth is 80%.
NOTE: Do not exceed the specified input level that causes 100% depth, or the
Transmitter’s modulation limiting circuits will cause added distortion. Refer
to the input level specifications for the Transmitter being tested.
On the Radio:
9. Key the Transmitter and keep keyed until reading displays.
Distortion (in percent, or dB) is displayed on the Test Set as shown.
TX TEST
AM Depth
TX Frequency
TX Power
Distn %
%
W
MHzH
Distortion
28.310176
18.3 12.8
98.9
Depth