High Quality Video Capture and Storage Capacity.

  • 4 – Analog channels & 2 IP channel
  • H.264 video compression
  • Dual Streaming
  • Analog channels support 960H res standard & AHD
  • Up to 2TB HDD or SSD available
  • Fanless Design & integrated lock box
  • Wireless Ready – WiFi & Cellular
  • MIL SPEC 810F compliant shock and vibration

The G4-504HD2a is a 6 channel (4 AHD, 2 IP) recorder. Each analog channel will record 10 FPS simultaneously with independently selectable resolutions quality levels. The 504HD2a supports hard drives sizes up to 2TB and SSD up to 2TB.

Superb Reliability

The G4-504HD2a incorporates many features that dramatically increase the reliability of the DVR, and the availability of recorded video.

The G4-504HD2a has a high capacity power supply. The power supply stores energy so that if the DVR loses power (when the engine is started or other high current draw electrical devices are turned on, such as air conditioners or hydraulic lifts), there is enough energy in the power supply to continue to power the internal circuits of the DVR for a short period of time. For example, when power to the DVR is lost the DVR closes the video files correctly and then power down into a safe low power state. This makes the DVR virtually immune to the notorious unreliable power found in vehicles.

The G4-504HD2a has a latched door that prevents users from inadvertently removing the Caddy (hard drive carrier) before powering down the DVR.

The key must first be turned to the unlock position before the door can be unlatched and opened and the caddy can be removed. When the door is unlatched and opened, the DVR shuts down, and it is safe to remove the Caddy. After the Caddy is reinserted, and the door is closed and latched, the DVR reboots and is once again ready to record.

Built Rugged

The Caddy incorporates a shock and vibration system to protect the hard drive. It has passed MIL SPEC 810F (Trucks on Streets) for shock and vibration. In addition, Gatekeeper has developed and subjected the Gatekeeper DVRs to custom shock and vibration profiles. These profiles were derived by placing sensors on vehicles, and recording the shock and vibration that actual DVRs were subjected to in real world conditions.

For the ultimate in hard drive reliability, the Caddy can be equipped with a 2TB Solid State Hard Drive.

The Caddy contains an advanced thermal management system that heats up the hard drive to its prescribed operating temperature, before writing or reading data in cold weather.

Download of Video to a USB Drive

The G4-504HD2a allows the user to download video, and/or video of marked events, to a USB memory stick that can be inserted in the front of the DVR.

WiFi and Auto Wake Ready

The G4-504HD2a is WiFi Ready. Gatekeeper’s WiFi system will provide radio coverage in a typical vehicle yard.

Utilizing WiFi 802.11n at 5GHz, Gatekeeper offers both a rugged industrial rated access point, and a WiFi radio for the vehicle. Through the use of Auto Wake, a user can turn on the DVR and WiFi radio in the vehicle, so that video can be accessed.

Dual Streaming and Cellular Ready

The 504HD2a is dual streaming. This means a high quality full resolution image can be stored on the Caddy, while a lower resolution image can be streamed over the optional cellular connection.

Full Complement of Peripherals Available

The following optional peripherals are available:

• Driver Alert Button with Status LEDs
• Rear cable cover
• Interactive Control Display
• External G Sensor
• 4 Port Hub

System Specifications: 504HD2a Mobile Digital Video IP Recorder
     Video Channels 4 Analog High Definition / Standard Definition channels and 2 IP channels

With addition of 4 port switch:

4 Analog High Definition / Standard Definition channels and 4 IP channels

     Output  1 channel
     Video Compression  H.264
     Video Quality  User configurable – 8 leves (1 is the best quality)
     Video System  NTSC/PAL 75 ohm
     Resolution IP: Camera Dependent

1080p (1920×1080)

720p   (1280×720)

AHD: 1080p (1920×1080)

720p   (1280×720)

WD1 (928×480), WHD1 (928×240), WCIF (464×240),

HD1(704×240), CIF (352×240)

NTSC:WD1 (928×480), WHD1 (928×240), WCIF (464×240),

HD1(704×240), CIF (352×240)

PAL: WD1 (928×576), WHD1 (928×288),WCIF (464×288),

D1 (704×576), HD1 (704×288), CIF (352×288)

Video Resource 4 channels @ 6 FPS 720P(AHD), 2 Channels @ 30 FPS 1080P (IPC)


4 Channels @ 10 FPS 1080P(AHD), 2 Channels 30 FPS 1080P(IPC)


     On Screen Display  User configurable
     Video Streams  Dual Streaming
     Audio Channels  4 analog channels and 2 via IP
     Output  1 channel
     Audio Compression  ADPCM
 Storage  Removable Hard Drive – Up to 2TB HD or SSD

1 SD Card: 32GB, 64GB, 128GB & 256GB

     Recording Trigger  Recording Trigger Schedule, Alarms, Sensor Triggers
     Pre recording  0 to 60 min
     Post recording  Max 30 min
     File Size  15 min of video
     DVR Video Playback  1 channel local Up to 6 (8)channels using G4 Viewer Plus
     Search Method  Date/Time, channel, event
     Backup Mode  USB
     Ethernet  Ethernet RJ 45 port (10/100M) Optional
     Cellular  Optional external 3G or 4G cellular module
     WIFI 802.11ac 5GHz external, optional
     GPS  GPS Location, Speed, Time Sync
     Input  Input 8 to 36v
     Output 5V @ 500mA, 12V@500mA
     Standby Current  <1 mA @ 12.6V
 8.5” x 6” x 3.5” (215 mm x 150 mm x 80 mm) without cable cover

11.5” x 6” x 3.5” (280 mm x 150 mm x 80 mm) with cable cover (Optional)

     Weight  4.4lbs (2kgs)
     Operating Temperature  -40°F – 158°F (-40°C to +70°C)
     Humidity  Below 90% non-condensing

504HD2a Product Sheet