Agilent Technologies 8360B, User Manual, Page: 271 / 496

FM Modulation
O VERMOD Message (Maximum Deviation)
The maximum FM deviation is limited b y the following t w o
conditions:
Maximum FM deviation m ust b e less than 8 MHz and
Maximum FM deviation m ust b e less than n x 5 x FM rate
(refer to the \F requency Bands" sp ecication for the v alue of n).
The following c hart sho ws the limits of eac h band given these t w o
conditions.
F or example, in band 1 at a 1 MHz FM rate, the FM deviation m ust
b e less than 5 MHz.
n (1) x 5 x FM Rate (1 MHz) = 5 MHz.
The FM rate can b e decreased as long as the FM deviation remains
less than n x 5 x FM rate and less than 8 MHz.
Figure M-3. FM Deviation and Rate Limits
If the FM deviation is set greater than the 8 MHz limit, it m ust
b e decreased for sp ecied p erformance. An OVERMOD message is
display ed on the message line if the FM deviation exceeds
n x 5 x FM rate. Then, either decrease the FM deviation or increase
the FM rate un til b oth conditions for FM deviation are met.
A t FM rate lev els greater than those sho wn for eac h band
corresp onding to the 8 MHz FM deviation lev el, the n x 5 x FM
rate v alue will alwa ys b e greater than 8 MHz so the maximum FM
M-18 Operating and Programming Reference