Will cell phone jammer be switched off during the rest between classes?

The company has developed the second generation of     cell phone jammer     specific to examination room.
MIDI is short for Musical Instrument Digital Interface, which means Musical Instrument Digital Interface. It is an electronic musical instruments and electronic instruments and computers between the unity between the exchange agreement. MIDI file format audio files, also known as frequency synthesis, which is synthesized by the frequency of the audio files stored symbol (control information) on the control of Sound Blaster audio synthesizer output audio signal coding and time, simply, is itself can not occur, you need the A / D converter sound card drivers. MIDI is Musical Instrument Digital Interface (MusicalInstrument Digital Interface) of the abbreviation. So MIDI is not a real thing, but an internationally accepted standard interface. Through it, various MIDI devices can be accurately transmitted MIDI messages. Advantages: MIDI file does not contain information about streaming media, file size smaller, the sound quality is quite good. Disadvantages: MIDI file is not a real sense of the audio files, but the audio control file, do not support live original music or voice. Will cell phone jammer be switched off during the rest between classes?
Can be pure MIDI, but also PCM (pure vocal), also is PCM + MIDI (voice + MIDI). Actual manifestations of MFM format is mfmp, which is defined by ROHM chip format, fully taking into account the characteristics of mobile devices. Modified the original MIDI file, the conversion tools provided by ROHM direct conversion or by midi + wav files generated after synthesis, is added wav sound files. It does not distinguish between the number of how many chords. Now I know part of the series phone supports Panasonic mfm format ringtones. Advantages: data capacity is small, the file can be compressed, and can be reduced more than half have adapted to the phone's CPU processing power is weak, the lack of storage capacity of small points. Multimedia extensions, can be extended on the SMAF portrait, text, sound, multimedia functions. Can function independently of management at the same time, its all embedded in a file. The vertical suppression beam-width of   cell phone jammer is 120°.
MMF SMAF format, also known as the format, it is YAMAHA has introduced a more common format of mobile phone bell field, domestic common with MA2 (16 chords), MA3 (40 chords), MA5 (64 chords) three. MMF format features: MMF ringtone format can be said is the world's best. The format inclusive great support depending on the phone configuration, support for polyphonic, respectively, wave, speech synthesis and so on. MMF format to support the voice part of the sampling rate: MA2: 4000Hz, 8000Hz. Which is mainly used for low frequency audio playback 4000Hz, 8000Hz suitable for making a real feel of the sung tone of voice production. MA3, 5: support 6000/8000/16000Hz frequency sampling. Advantages: data capacity is small, the file can be compressed, and can be reduced more than half have adapted to the phone's CPU processing power is weak, the lack of storage capacity of small points. Multimedia extensions, can be extended on the SMAF portrait, text, sound, multimedia functions. Can function independently of management at the same time, its all embedded in a file. It is not appropriate to leave     cell phone jammer    in the direct sunlight or the hot, wet or dusty area, which may shorten lifetime of     cell phone jammer    .