Specifications Overview
The document outlines the specifications for a series of mobile DVR models: CV-MR4210, CV-MR4211, CV-MR8210, and CV-MR8211. These devices support 4/8 channel 1080P recording and are equipped with GPS and G-Sensor capabilities. They offer storage options including a 2.5" SSD with a maximum capacity of 1TB and support for SDXC cards up to 256GB for event and backup recording.

Power and Connectivity
The devices operate on a wide range of DC power input from 8V to 36V and support battery recording. They also provide power output to cameras and feature a panic button. Connectivity options include 4G/Wi-Fi functions, two-way audio/message capabilities, and hotspot features for specific models (MR4210/MR8210).

Technical Specifications
The DVRs run on an Embedded Linux 3.0.x OS and support HD video input via AHD/TVi and analog video input via CVBS. They have a signal-to-noise ratio of over 40dB and support video loss detection indicated by an LED. Audio input ranges from 0.5 to 1.4Vp-p@20k. The devices support multiple languages including English, Traditional Chinese, and Japanese.

Recording and Playback
The DVRs feature a real-time clock with GPS time calibration and daylight saving support. They include hardware and software watchdogs for system monitoring and automatic recovery features. Ignition-off recording can be set from 30 seconds to always on. Playback is supported via a PC viewer program with AVI conversion, and playback modes include event and time search.

Compression and Quality
Video is compressed using the H.264 high-profile format, while audio uses PCM (Alaw 8KHz). Recording quality can be set to low, normal, or high, with resolutions available in HD (1080P/720P/960H) and D1 (NTSC/PAL). Frame rates per channel are 30fps for 1080P, 720P, and 960H, and 30fps (NTSC) or 25fps (PAL) for D1.

Additional Features
The devices support automatic overwrite and have a display resolution of D1: 720x480 (NTSC) or 720x576 (PAL). Communication interfaces include RS232, GPIO, and USB ports. Network protocols supported are DHCP, HTTP, TCP/IP, SMTP, RTP, and RSTP. GPS is supported via a G-Mouse type with NMEA 0183 protocol, and a 3-axis G-force sensor is included.

Environmental and Physical Specifications
The operating temperature range is -30 to +60℃ without SSD. The dimensions of the devices are 193mm (W) x 89mm (H) x 202mm (D).