HP 8360 User Manual
Page 264
FM Modulation
The FM rate can be decreased as long as the FM deviation remains
less than n x 5 x FM rate and less than 8 MHz.
Figure
FM Deviation and Rate Limits
If the FM deviation is set greater than the 8 MHz limit, it must
be decreased for specified performance. An
message is
displayed 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 until both conditions for FM deviation are met.
At FM rate levels greater than those shown for each band
corresponding to the 8 MHz FM deviation level, the n x 5 x FM
rate value will always be greater than 8 MHz so the maximum FM
deviation is no longer limited by the FM rate, only by the maximum
limit of 8 MHz.
Operating and Programming Reference
HP 8360
User’s Handbook