Product: HDMI to BNC Converter Video Adapter - HDMI in Female BNC Coax Out Connector Composite Box with 3.5mm Audio Output for Full HD DVD DVR PS4 Wii Game Image to Coaxial Analog CVBS Signal Camera Monitor TV
Brand: AoeSpy
HDMI to BNC video converter is an adapter for full HDMI equipment sources which are from TV box , game console ( PS3 / PS4 / WII U / XBOX One 360 ), ordinary cameras , Blue-ray DVD Player or high-definition player etc. transforming into BNC CVBS output or converting the audio and video signals of NTSC / PAL format to 480P / 576I analog signals which are used on normal old TV / Monitor / VCR / DVR / VHS etc.devices . It widly applicate to KTV equipment or meeting / presentation that converts full HD camera signals to the video recording capture card of computer for remote control( HTTP ) or web conferencing meeting
Will this convert the hdmi input from a roku device and convert and output to bnc (coax)? 
Yes, this hdmi in coaxial bnc out adapter will convert the hdmi input from a roku device and convert output to bnc ( coaxial ) , but please note that the audio output of roku device is by 3.5 mm stereo（L/R）output on this converter .
Confirm the source device is BNC CVBS analog signal with coax connector port , NOT the coax RF / antenna connector port and  AHD / TVI / CVI analog signal or SDI digital signal , Please don't use it for AHD to HDMI , TVI to HDMI , CVI to HDMI or SDI to HDMI; 
Check all the cables by direct connect with source and display.Check the power supply to see if it has electricity or the light is lihgting. 
Specs: 
Input: HDMI / MHL
Output: BNC & 3.5 mm stereo（L/R）
Support Input Video Format: PAL / NTSC
HDMI Input Resolution：480P, 576P,720P,1080I,800x600,1024x768,1280x720,1280x1024,1080P@60Hz
Compatible with HDMI1.3 ,support HDCP 2.0
BNC Output Resolution：480P or 576I（optional）
Picture Output Resolution： 4:3 or 16:9（optional）
Power: DC/5V 
Packages
1x HDMI to BNC Converter 
1x Power Adapter
1x User Manual 
HDMI to BNC Converter - Convert the high-definition video and audio signals from TV box , game console (PS3 / PS4 / WII U / XBOX One 360 ), ordinary cameras , Blue-ray DVD Player or high-definition player etc. to coaxial BNC analog sigals which are used on normal old TV / Monitor / VCR / DVR etc. devices .( Note: This signal converter ONLY works with CVBS signal , DOES NOT with AHD / TVI / CVI analog signal or SDI digital signal ,Does Not Support AHD / TVI / CVI and SDI )
HDMI to BNC - Transmit Full HD digital signals ( NTSC / PAL) format to BNC (480P / 576I ) Composite video sigial ( CVBS ) output through the video processing of scale down ; Enhance the image brightness , contrast and color with high-definition video processing technology that makes the transmittance of converted BNC image fully .
HDMI to BNC Adapter - Convert hdmi digital audio to 3.5 mm stereo（L/R）analog audio signal through the processing of DAC digital chip .
HDMI BNC Coax Connector - Compatible with HDCP signal and recognize HDCP Automatically .
HDMI BNC Composite Box for TV - Support 4:3 and 16:9 switch Real restore the squashed 4:3 picture shown on the 16:9 tv ; Plug and Play , easy to use .

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