Specifications: Noise Limited Sensitivity: FM  (S/N=30dB):FM <3uV.  MW (S/N=26dB):MW < 1mV/m.  LW  (S/N=26dB):LW <5mV/m.  SW  (S/N=26dB):SW < 20uV.  SSB (S/N=10dB):SSB < 1uV.  AIR  (S/N=10dB):AIR <5uV.  Signal-noise ratio(SNR/S/N).  FM: < 60dB.  MW/LW: < 45dB.  SW: < 50dB.  Frequency coverage: FM：76-108MHz/87-108MHz.  MW: 522-1620KHz/520-1710KHz.  LW: 100-519 KHz .  SW: 1711-29999 KHz .  AIR: 118-137 MHz .  Dimension:18.7x11.4x3.3cm(WxLxH).  Power supplies: Built-in 4×AA(UM3) size Ni-Mh rechargeable batteries Built in DC 5V USB jack, Earphone jack.     Features: It can receive FM stereo, medium wave, long wave, short wave, short wave single sideband communication signal and aviation band signal, with high sensitivity, good selectivity, beautiful sound quality, and convenient operation.  The FM receiving range is 76-108MHz, which can receive FM radio frequencies in China, Europe, America and Japan. It can also receive some domestic campus broadcast frequencies and TV sounds Short-wave single-sideband (SSB) sub-band and lower sideband (LSB) independent reception.  Frequency modulation uses synchronous detection and secondary frequency conversion technology to greatly improve the sensitivity of listening, selectivity, and anti-mirror, adjacent channel interference It has an FM/short-wave external antenna jack and a high/medium/low 3-speed sensitivity control switch for remote reception (DX).  Manual, semi-automatic, fully automatic (ATS) storage of up to 2000 radio frequencies. Among them, 800 are stored by the band (100 in frequency modulation/medium wave/long wave/aviation band, and 200 in short wave/single sideband). The remaining 1200 frequencies are not randomly stored in 12 pages (12x100).  High quality and high sensitivity speaker, good tone; high/bass control switch for listening to different programs; earphones for FM stereo broadcast.  The man-machine interface is friendly and easy to use and has a very practical multi-function digital adjustment knob that can be used to set the time. Adjust the frequency. Select the storage page and address.  Dual-time power-on function, and power-on to receiving radio programs with pre-stored frequencies.  The intelligent switch machine can be set to automatically shut down after 1-120 minutes of power-on, or cancel the automatic power-off function.  Six-channel selection methods: Manually search for the station frequency (VF).  Input the frequency number directly.  Manually search for pre-stored stations (VMs).  Directly enter the pre-stored station address number.  Automatically search for the station frequency.  Automatically search for stored station frequency.     Package Included:  1 x PL-660 Radio.  1 x External Antenna.  1 x Earphone.  1 x User Manual