Sec. 90.237  Interim provisions for operation of radioteleprinter and 
          radiofacsimile devices.

    These provisions authorize and govern the use of radioteleprinter 
and radiofacsimile devices for base station use (other than on mobile-
only or paging-only frequencies) in all radio pools and services except 
Radiolocation in this part.
    (a) Information must be submitted with an application to establish 
that the minimum separation between a proposed radioteleprinter or 
radiofacsimile base station and the nearest co-channel base station of 
another licensee operating a voice system is 120 km. (75 mi.) for a 
single frequency mode of operation, or 56 km. (35 mi.) two frequency 
mode of operation. Where this minimum mileage separation cannot be 
achieved, either agreement to the use of F1B, F2B, F3C, G1B, G2B or G3C 
emission must be received from all existing co-channel licensees using 
voice emission within the applicable mileage limits, or if agreement was 
not received, the licensee of the radioteleprinter or radiofacsimile 
system is responsible for eliminating any interference with preexisting 
voice operations. New licenses of voice operations will be expected to 
share equally any frequency occupied by established radioteleprinter or 
radiofacsimile operations.
    (b) The application must list the manufacturer and model number of 
the radioteleprinter or radiofacsimile system to be employed, or contain 
a detailed technical description of the system.
    (c) Transmitters type-accepted under this part for use of G3E or F3E 
emission may also be used for F1B, F2B, F3C, G1B, G2B or G3C emission 
for radioteleprinter or radiofacsimile, provided the keying signal is 
passed through the low pass audio frequency filter required for G3E or 
F3E emission. The transmitter must be so adjusted and operated that the 
instantaneous frequency deviation does not exceed the maximum value 
allowed for G3E or F3E.
    (d) Frequencies will not be assigned exclusively for F1B, F2B, F3C, 
G1B, G2B or G3C emission for radioteleprinter or radiofacsimile (except 
where specifically provided for in the frequency limitations).
    (e) The requirements in this part applicable to the use of G3E or 
F3E emission are also applicable to the use of F1B, F2B, F3C, G1B, G2B 
or G3C emission for radioteleprinter and radiofacsimile transmissions.

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    (f) The station identification required by Sec. 90.425 must be given 
by voice or Morse code.
    (g) For single sideband operations in accordance with Sec. 90.266, 
transmitters type-accepted under this part for use of J3E emissions may 
also be used for A2B and F2B emission for radioteleprinter 
transmissions. Transmitters type-accepted under this part for use of J3E 
emissions in accordance with Secs. 90.63(d)(1), 90.65(c)(1), 90.73(d)(1) 
and 90.81(d)(13) may also be used for A1B, A2B, F1B, F2B, J2B, and A3C 
emissions to provide standby backup circuits for operational 
telecommunications circuits which have been disrupted, where so 
authorized in other sections of this part.
[ 43 FR 54791 , Nov. 22, 1978, as amended at  49 FR 48712 , Dec. 14, 1984; 
 51 FR 14998 , Apr. 22, 1986;  62 FR 18927 , Apr. 17, 1997]

    Effective Date Note: At  62 FR 18927 , Apr. 17, 1997, Sec. 90.237 was 
amended by revising the introductory text, effective Oct. 17, 1997.