§ 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
   t1^4 ±25.0 kHz 5.0 ms 10.0 ms
   t2 ±12.5 kHz 20.0 ms 25.0 ms
   t3^4 ±25.0 kHz 5.0 ms 10.0 ms
   Transient Frequency Behavior for Equipment Designed to Operate on 12.5 kHz
   Channels
   t1^4 ±12.5 kHz 5.0 ms 10.0 ms
   t2 ±6.25 kHz 20.0 ms 25.0 ms
   t3^4 ±12.5 kHz 5.0 ms 10.0 ms
   Transient Frequency Behavior for Equipment Designed to Operate on 6.25 kHz
   Channels
   t1^4 ±6.25 kHz 5.0 ms 10.0 ms
   t2 ±3.125 kHz 20.0 ms 25.0 ms
   t3^4 ±6.25 kHz 5.0 ms 10.0 ms

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

   t1 is the time period immediately following ton.

   t2 is the time period immediately following t1.

   t3 is the time period from the instant when the transmitter is turned off
   until toff.

   toff is the instant when the 1 kHz test signal starts to rise.

   ^2 During the time from the end of t2 to the beginning of t3, the frequency
   difference must not exceed the limits specified in § 90.213.

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

   ^4 If 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]

   return arrow Back to Top