§ 95.1779   GMRS unwanted emissions limits.

   Each GMRS transmitter type must be designed to comply with the
   applicable unwanted emissions limits in this section.

   (a) Emission masks. Emission masks applicable to transmitting equipment
   in the GMRS are defined by the requirements in the following table. The
   numbers in the attenuation requirements column refer to rule paragraph
   numbers under paragraph (b) of this section.
   Emission types filter Attenuation
   requirements
   A1D, A3E, F1D, G1D, F2D, F3E, G3E with audio filter (1), (2), (7)
   A1D, A3E, F1D, G1D, F3E, G3E without audio filter (3), (4), (7)
   H1D, J1D, R1D, H3E, J3E, R2E (5), (6), (7)

   (1) Filtering noted for GMRS transmitters refers to the requirement in
   § 95.1775(e).

   (2) Unwanted emission power may be measured as either mean power or
   peak envelope power, provided that the transmitter output power is
   measured the same way.

   (b) Attenuation requirements. The power of unwanted emissions must be
   attenuated below the transmitter output power in Watts (P) by at least:

   (1) 25 dB (decibels) on any frequency removed from the center of the
   authorized bandwidth by more than 50% up to and including 100% of the
   authorized bandwidth.

   (2) 35 dB on any frequency removed from the center of the authorized
   bandwidth by more than 100% up to and including 250% of the authorized
   bandwidth.

   (3) 83 log (fd ÷ 5) dB on any frequency removed from the center of the
   authorized bandwidth by a displacement frequency (fd in kHz) of more
   than 5 kHz up to and including 10 kHz.

   (4) 116 log (fd ÷ 6.1) dB or 50 + 10 log (P) dB, whichever is the
   lesser attenuation, on any frequency removed from the center of the
   authorized bandwidth by a displacement frequency (fd in kHz), of more
   than 10 kHz up to and including 250% of the authorized bandwidth.

   (5) 25 dB on any frequency removed from the center of the authorized
   bandwidth by more than 50% up to and including 150% of the authorized
   bandwidth.

   (6) 35 dB on any frequency removed from the center of the authorized
   bandwidth by more than 150% up to and including 250% of the authorized
   bandwidth.

   (7) 43 + 10 log (P) dB on any frequency removed from the center of the
   authorized bandwidth by more than 250%.

   (c) Measurement bandwidths. The power of unwanted emissions in the
   frequency bands specified in paragraphs (b)(1) through (4) of this
   section is measured with a reference bandwidth of 300 Hz. The power of
   unwanted emissions in the frequency range specified in paragraph (b)(5)
   of this section is measured with a reference bandwidth of at least 30
   kHz.

   (d) Measurement conditions. The requirements in this section apply to
   each GMRS transmitter type both with and without the connection of
   permitted attachments, such as an external speaker, microphone, power
   cord and/or antenna.

   return arrow Back to Top