8
can connect the low impedance earphone and active sound box or other audio output equipments
through power amplifier. If the sound box and the tone arm can not be isolated, howling
phenomena is often existed. There are some methods to deal with the above phenomena.
1. Adopt better directional tone arm.
2. Adjust the sound box volume to be under the threshold that produces the howling
phenomena.
3. Use fitment materials that absorb the sound to reduce reflection of the sound.
4. Adjust the layout of the sound box and the tone arm.
1.9 Technical parameters
Type
4ch
8ch
16ch
System
Main processor
High performance embedded microprocessor
Operation system
Embedded LINUX operation system
System resource
synchronous multi-channel recording, synchronous multi-channel
sub-code stream, synchronous multi-channel playback, synchronous
network operation
Interface
Operation interface
16 bit true color graphical menu interface, mouse operation supportive
display
¼ image display
1/4/8/9 image display
1/4/8/9/16 image display
Video
Video standard
PAL 625line,50 f/s; NTSC 525 line,60 f/s
Surveillance image
quality
PAL, D1(704x576);NTSC, D1(704x480)
Playback image
quality
PAL,D1(704×576);NTSC, D1(704*480)
Video compression
H.264 mp
Video control
6 options
Recording speed
100/120fps (D1)
200/240fps (CIF),
50/60fps D1
400/480fps CIF
Motion detect
192(12×16) detection areas, multiple sensitivity
Audio
Audio compression
G711A
Bi directional Talk
Support
Record
And
Recording mode
manual > alarm > motion detect > timing
Playback
Any channels playback, multiple channels playback
