| Model
 | DVR2104 | 
        
          | Video    Compression | Modified MJPEG (12-20K bytes/frame) | 
        
          | Video System | NTSC / PAL | 
        
          | Operation System | Stand-alone | 
        
          | Video Input / Output | BNC 4-channel / BNC 2-channel | 
        
          | Display Frame Rate | NTSC: 120 fps / PAL: 100 fps | 
        
          | Recording Frame Rate | NTSC: Max. 30 fps / PAL: Max. 25 fps  | 
        
          | Record Mode | Continuous / time schedule / motion    detection / sensor triggered | 
        
          | Display Resolution | NTSC: 720 x 480 / PAL: 720 x 576 | 
        
          | Record Resolution | NTSC: 320 x 112, 640 x 224 / PAL: 320 x    136, 640 x 272 | 
        
          | HDD Interface | One fixed HDD rack, supports up to 500GB    IDE HDD | 
        
          | Estimated Record Length  | 250GB Hard drive @ 25fps @ Normal Quality(250x1024x1024 K byte) / ( 25x15x60x    60) = 194 Hours
 | 
        
          | Playback Search | Time & Date, Event List | 
        
          | Display Mode | Each, Quad, Auto-switch | 
        
          | USB | For PC playback & backup / USB 2.0 | 
        
          | PTZ | Built-in RS-485 port | 
        
          | Sensor & Alarm | 4-channel inputs / 1-channel output | 
        
          | Remote Control | Included | 
        
          | Power Supply | DC12V, 3A (adaptor included) | 
        
          | Dimension | 300mm(W) x 220mm(D) x 47mm(H) |