What is Family Radio Service (FRS)?

The Family Radio Service (FRS) is an improved walkie talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies in the ultra high frequency (HF) band. It does not suffer the interference effects found on citizens' band (CB) at 27MHz, or the 49MHz band also used by cordless phones, toys and baby monitors. FRS uses frequency modulation (FM) instead of amplitude modulation (AM). Since the UHF bands has different radio propagation characteristics, short-range use FRS may be more predictable than license-free radios operating in the HF CB band.

Using FRS (Family Radio Service)

FRS radios are limited to 500 milliwatts according to FCC channels. Channel 1 to 7 are shared with low-power interstitial channels of GMRS, the General Mobile Radio Service. A license is required for those channels if the power output is over FRS limits.

What are Japan FRS Limititation?

In Japan, a similar service is limited to 10 milliwatts in the 420, 421, and 422 MHz bands.

It is called "Tokutei Shoudenryoku Musen" or "Scpecified Low Power Radio (SLPR) ".
422.0500 - 422.1750MHz (Business use) 10mW 11ch 12.5kHz spacing.
422.200 - 422.300MHz (Leisure use) 10mW 9 channels 12kHz spacing.

License free radio system.

Japanese License Free Radio System is well-grounded in Article 4 in the law about the radio rule of Japan that was established in 1950.