Don't forget to enter settings and change the screen resolution from 480i to 480p. If you switch the Wii to 480p mode, they may work in an HDMI compatible manner. Output resolution: 720p / 1080p (whether the high resolution can be achieved depends on the input signal).
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hdmi to rca av adapter converter hdmi2av ntsc pal full hd for ps3 for ps4 for xbox 60 hz for tv box compactible hdmi spli
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For Wii To HDMI-compatible Adapter Converter 3.5mm Audio For PC HDTV Monitor 1080P 720P Wii2 To HDMI WII2HDMI Converter Adapter. Full HD 1080P Wii to HDMI-Compatible Converter Adapter Wii to HDMI-Compatible Converter 3.5mm Audio for PC HDTV Monitor Display.
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HD 1080P RCA AV to HDMI Converter Mini AV to HDMI RCA Composite CVBS Video Audio Adapter for PS2/3 VCR DVD to TV with USB Cable
Aliexpress UK
For Wii to HDMI-compatible converter: convert for Wii input to HDMI-compatible HD output to provide more realistic HD visual effects. Support for Wii all display modes (NTSC 480i, PAL 576i) Note: for Wii Mini is not supported,male to male ,do need buy wii/hdmi cable.
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HDMI to RCA, AV,1080P HD HDMI to 3RCA CVBs Composite Video Audio Converter Adapter Supports PAL/NTSC for Fire TV
Aliexpress UK
RUOVXWU Wii to HDMI Adapter, Wii to hdmi Converter, wii to hdmi1080p 720p Connector Output Video & 3.5mm Audio - Supports All Wii Display Modes. Compatibility Mode: Note: Not compatible with Wii Mini.
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HDMI to AV Converter HDMI to RCA Adapter 1080P Convert Cord Transmitter Connection function Video Component Cable 1m/3ft HD TV
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It outputs video and audio in full digital HDMI format and supports all Wii display modes (NTSC 480i 480p, PAL 576i). If it does not, or the minimum resolution is 1080p, it will just show a black screen.
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1080P RCA AV To HDMI-compatible Composite Adapter Converter Audio Video Cable HDMI-compatible TO AV with USB Cable for HD TV BOX
Aliexpress UK
1 x Wii to HDMI-Compatible Converter. Input: For Wii AV Connector. High quality, state of the art motion adaptive de-interlacing for 480i ,576i input. Output: 3.5mm Jack Audio/ HDMI-Compatible Connector.
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1080P 1.5M HDMI-compatible to 3 RCA Video Audio HDMI-compatible Cable AV Cord Converter Adapter For TV Set-Box DVD Laptop
Aliexpress UK
Small in Size: PORTHOLIC Wii to HDMI Adapter with size of 6 x 3 x 1.9cm, is small but powerful. It does not occupy any space on your table by hooking up the back of Wii. No more tangling cords, just one cable.
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AV to HDMI-compatible Converter HD 1080P RCA AV to HDMI-composite CVBS Video Audio Adapter for PS2/3 DVD to TV with USB Cable
Aliexpress UK
Manufacturer : PORTHOLIC. Small in Size: PORTHOLIC Wii to HDMI Adapter with size of 6 x 3 x 1.9cm, is small but powerful. It does not occupy any space on your table by hooking up the back of Wii. No more tangling cords, just one cable.
eBay
1080P HDMI-Compatible AV Audio Adapter HD Video Converter Box HDMI-Compatible to RCA AV Video 1080P Support NTSC PAL for PS3
Aliexpress UK