FCC 90.214
Revised as of September 29, 2014
Goto Year:2013 | 2015
```§ 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.

^2 During 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.

^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]