Part 15

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(15.235 Operation within the band 49.82-27.90 MHz.)
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(d) Cordless telephones are not permitted to operate under the provisions of this section.
(d) Cordless telephones are not permitted to operate under the provisions of this section.
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49 MHz walkie talkies, baby monitors and low-power RC devices operate within the 49 MHz frequency band.  The de facto five frequencies are 49.830 MHz, 49.845 MHz, 49.860 MHz, 49.875 MHz and 49.890 MHz.  However, there are no specific channel plans for this band.  For more information see the [[Remote_Control#49_MHz_RC_Frequencies|49MHz section of the remote control page on this wiki]].
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49 MHz walkie talkies, baby monitors and low-power RC devices operate within the 49 MHz frequency band.  The de facto five frequencies are 49.830 MHz, 49.845 MHz, 49.860 MHz, 49.875 MHz and 49.890 MHz.  However, there are no specific channel plans for this band.  For more information see the [[Remote_Control#49_MHz_RC_Frequencies|49MHz section of the remote control page on this wiki]].  For example, the Maxon Communicator series of portable transceivers (walkie-talkies) such as Maxon the PC-50 and the Radio Shack TRC-509, TRC-512 and TRC-503 49 MHz FM walkie talkies use these frequencies with approximately 10mw transmitter output power.
[[Category: Radio station lists]]
[[Category: Radio station lists]]

Revision as of 18:47, 12 July 2019

Part 15 is the section of FCC regulations dealing with unlicensed radio operation. Operation in several bands is allowed:


Contents

15.217 Operation in the band 160-190 kHz.

(a) The total input power to the final radio frequency stage (exclusive of filament or heater power) shall not exceed one watt.

(b) The total length of the transmission line, antenna, and ground lead (if used) shall not exceed 15 meters.

(c) All emissions below 160 kHz or above 190 kHz shall be attenuated at least 20 dB below the level of the unmodulated carrier. Determination of compliance with the 20 dB attenuation specification may be based on measure- ments at the intentional radiator's antenna output terminal unless the in- tentional radiator uses a permanently attached antenna, in which case com- pliance shall be demonstrated by measuring the radiated emissions.



15.218 Operation in the band 510-1705 kHz.

(a) The total input power to the final radio frequency stage (exclusive of filament or heater power) shall not exceed 100 milliwatts.

(b) The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters.

(c) All emissions below 510 kHz or above 1705 kHz shall be attenuated at least 20 dB below the level of the unmodulated carrier. Determination of compliance with the 20 dB attenuation specification may be based on measure- ments at the intentional radiator's antenna output terminal unless the in- tentional radiator uses a permanently attached antenna, in which case com- pliance shall be demonstrated by measuring the radiated emissions.



15.221 Operation in the band 525-1705 kHz.

(a) Carrier current systems and transmitters employing a leaky co- axial cable as the radiating antenna . . . .



15.225 Operation within the band 13.553-13.567 MHz.

(a) The field strength of any emissions within this band shall not exceed 10,000 microvolts/meter at 30 meters.

(b) The field strength of any emissions appearing outside of this band shall not exceed the general radiated emission limits shown in 15.209.

(c) The frequency tolerance of the carrier signal shall be maintained within +/- 0.01% of the operating frequency over a temperature variation of -20 degrees to +50 degrees C at normal supply voltage, and for a variation in the primary supply voltage from 85% to 115% of the rated supply voltage at a temperature of 20 degrees C. For battery operated equipment, the equip- ment tests shall be performed using a new battery.



15.227 Operation within the band 26.98-27.28 MHz.

(a) The field strength of any emission within this band shall not exceed 10,000 microvolts/meter at 3 meters. The emission limit in this paragraph is based on measurement instrumentation employing an average detector. The provisions in 15.35 for limiting peak emissions apply.

(b) The field strength of any emissions which appear outside of this band shall not exceed the general radiated emission limits in 15.209.

See also: the RC Radio Service, the CB Radio Service, and high power datalink systems that use 26-27 MHz

15.235 Operation within the band 49.82-27.90 MHz.

(a) The field strength of any emission within this band shall not exceed 10,000 microvolts/meter at 3 meters. The emission limit in this paragraph is based on measurement instrumentation employing an average detector. The provisions in § 15.35 for limiting peak emissions apply.

(b) The field strength of any emissions appearing between the band edges and up to 10 kHz above and below the band edges shall be attenuated at least 26 dB below the level of the unmodulated carrier or to the general limits in § 15.209, whichever permits the higher emission levels. The field strength of any emissions removed by more than 10 kHz from the band edges shall not exceed the general radiated emission limits in § 15.209. All signals exceeding 20 microvolts/meter at 3 meters shall be reported in the application for certification.

(c) For a home-built intentional radiator, as defined in § 15.23(a), operating within the band 49.82-49.90 MHz, the following standards may be employed:

(1) The RF carrier and modulation products shall be maintained within the band 49.82-49.90 MHz.

(2) The total input power to the device measured at the battery or the power line terminals shall not exceed 100 milliwatts under any condition of modulation.

(3) The antenna shall be a single element, one meter or less in length, permanently mounted on the enclosure containing the device.

(4) Emissions outside of this band shall be attenuated at least 20 dB below the level of the unmodulated carrier.

(5) The regulations contained in § 15.23 of this part apply to intentional radiators constructed under the provisions of this paragraph.

(d) Cordless telephones are not permitted to operate under the provisions of this section.

49 MHz walkie talkies, baby monitors and low-power RC devices operate within the 49 MHz frequency band. The de facto five frequencies are 49.830 MHz, 49.845 MHz, 49.860 MHz, 49.875 MHz and 49.890 MHz. However, there are no specific channel plans for this band. For more information see the 49MHz section of the remote control page on this wiki. For example, the Maxon Communicator series of portable transceivers (walkie-talkies) such as Maxon the PC-50 and the Radio Shack TRC-509, TRC-512 and TRC-503 49 MHz FM walkie talkies use these frequencies with approximately 10mw transmitter output power.