§  90.214   Transient frequency behavior.

   Transmitters designed to operate in the 150-174 MHz and 421-512 MHz
   frequency bands must maintain transient frequencies within the maximum
   frequency difference limits during the time intervals indicated:
   Time intervals ^1,2 Maximum
   frequency
   difference ^3 All equipment
   150 to 174 MHz 421 to 512 MHz
   Transient Frequency Behavior for Equipment Designed to Operate on 25
   kHz Channels
   t[1] ^4 ±25.0 kHz 5.0 ms 10.0 ms
   t[2] ±12.5 kHz 20.0 ms 25.0 ms
   t[3] ^4 ±25.0 kHz 5.0 ms 10.0 ms
   Transient Frequency Behavior for Equipment Designed to Operate on 12.5
   kHz Channels
   t[1] ^4 ±12.5 kHz 5.0 ms 10.0 ms
   t[2] ±6.25 kHz 20.0 ms 25.0 ms
   t[3] ^4 ±12.5 kHz 5.0 ms 10.0 ms
   Transient Frequency Behavior for Equipment Designed to Operate on 6.25
   kHz Channels
   t[1] ^4 ±6.25 kHz 5.0 ms 10.0 ms
   t[2] ±3.125 kHz 20.0 ms 25.0 ms
   t[3] ^4 ±6.25 kHz 5.0 ms 10.0 ms

   ^1[on]is the instant when a 1 kHz test signal is completely suppressed,
   including any capture time due to phasing.

   t[1]is the time period immediately following t[on].

   t[2]is the time period immediately following t[1].

   t[3]is the time period from the instant when the transmitter is turned
   off until t[off].

   t[off]is the instant when the 1 kHz test signal starts to rise.

   ^2During the time from the end of t[2]to the beginning of t[3], the
   frequency difference must not exceed the limits specified in §  90.213.

   ^3Difference between the actual transmitter frequency and the assigned
   transmitter frequency.

   ^4If the transmitter carrier output power rating is 6 watts or less,
   the frequency difference during this time period may exceed the maximum
   frequency difference for this time period.

   [ 62 FR 2040 , Jan. 15, 1997]

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