Press On/Off to turn AM on and off. The External
AM status display will reflect your selection as On
or Off; the AM modulation status area will reflect
your selection as External On or Off.
Press Edit Sensitivity to open the AM Sensitivity pa
-
rameter, then edit the current value using the cur
-
sor control keys, rotary data knob, or enter a new
value using the keypad and the appropriate termi
-
nator key (kHz/ms/STEPS for Linear; MHz/ms/dB
for Log). The AM Sensitivity range is 0 %/V to
100 %/V in Linear and 0 dB/V to 25 dB/V in Log. To
close the open AM Sensitivity parameter, press Edit
Sensitivity or make another menu selection.
Press Internal / External to select the source of the
modulating signal. Internal selects the modulating
signal from the internal AM generator; external se
-
lects the modulating signal from an external source.
The AM status display will reflect your selection.
Press Log / Linear to select the AM operating mode.
When Internal AM is active, the AM Depth display
will reflect your selection as XX dB (Log) or XX %
(Linear). When External AM is active, the AM Sen-
sitivity display will reflect your selection as XX dB/V
(Log) or XX %/V (Linear).
Press < Previous to return to the AM Status menu
display.
Frequency
Modulation
Operating
Modes
The signal generator has four FM operating modes:
Locked, Locked Low-Noise, Unlocked Narrow, and
Unlocked Wide. In the Locked and Locked
Low-Noise FM modes, frequency modulation of the
output signal is accomplished by summing the mod
-
ulating signal into the FM control path of the YIG
phase-lock loop.
In Locked FM mode, the maximum FM deviation is
the lesser of ±10 MHz or the rate times 300 for
1 kHz to 8 MHz rates. In Locked Low-Noise FM
mode, the maximum FM deviation is the lesser of
±10 MHz or the rate times three for 50 kHz to
8 MHz rates.
3-96 MG369XB OM
Signal Modulation Local (Front Panel) Operation
ERR
This error message is displayed
when the external AM modulating
signal exceeds the input voltage
range.The message “Reduce AM In
-
put Level” also appears at the bot
-
tom of the AM status display. AM is
turned off until the modulating sig
-
nal is within the input voltage
range.
