B&K Precision 4040A - Manual - Manual (Page 16)

16
OPERATING INSTRUCTIONS
Figure 6. Examples of AM modulation
3. Place the EXT MODULATION switch in the released position.
4. Connect a suitable modulating signal to the VCG/MOD INPUT jack on
the front panel.
5. Adjust the modulation level as described previously.
FM OPERATION
The output of the Model 4040 can be frequency-modulated, either by the
internal 1 kHz internal signal or by an external signal applied to the front
panel VCG/MOD INPUT jack.
Internal
1. Set the carrier frequency using the main FREQUENCY controls and
RANGE switches.
2. Engage the MODULATION ON switch and release the MODU-
LATION FM/AM switch.
3. Engage the INT MODULATION switch.
4. The amount of deviation can be varied by rotating the % M O D U -
LATION control.
External
1. Set the carrier frequency using the main FREQUENCY controls and
RANGE switches.
2. Engage the MODULATION ON switch and release the MODU-
LATION FM/AM switch.
3. Place the EXT MODULATION switch in the released position.