Take the RGB output from a Sinclair Spectrum +3 or +2A and output to an HDMI Monitor. NOT suitable for other Spectrum models that don't have an RGB output. Spectrum +3/+2A RGB to HDMI adaptor. "Works on ZX Spectrum +3 really well.
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Scart to HDMI cable RGB Scart to HDMI 1080P converter Scaler with Digital audio 2-in-1 HDMI+Scart RGB to HDMI AV converter
Aliexpress UK
HDMI to 3RCA Adapter -- This HDMI to 3RCA cable is used to signal transmit from a player to TV. It is also not possible to use the HDTV adapter to transfer this line to the TV. It works as a signal transmitter, not a signal converter.
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HDMI Extension Cable 4K 60Hz HDMI Exender cable Short HDMI 2.0 Male to Female cable extension HDMI port saver for Chrome cast
Aliexpress UK
HDMI to RCA cable is designed to connect and transfer signals from HDMI port to RCA port. b. HDMI to RCA cable is designed to connect and transfer (NOT CONVERT) signals from HDMI port to RCA port. This cable functions.
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Mini HDMI to HDMI Cable HDMI to Mini HDMI 4K 60Hz High Speed HDMI 2.0 Aluminum Shell Braided Cord Compatible for Monitor Camera
Aliexpress UK
HDMI compatible plug to 3 RCA audio video AV component cable. Fast connection and transmission of signals from HDMI compatible connector to RCA connector. unidirectional HDMI compatible input to 3 RCA output.
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AQ US Line Saint Dragon48 Dragon HDMI Cable High Definition Cable 8K10K TV Amplifier 4k Audio and Video Transmission Cable
Aliexpress UK
【1080P YPbPr to HDMI】The YPBPR to HDMI converter which will convert YPBPR video signal and the FL/FR stereo audio signals to HDMI video signal. To help user get the high quality of the HDMI video signal form the YPBPR signal.
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UGREEN HDMI Cable 4K/60Hz HDMI 2.0 Cable for RTX 3080 PS4 Xbox HDMI Splitter HDMI Switch Aux Ethernet cable 4K 3D Cable HDMI
Aliexpress UK
The AKORD HDMI to VGA SVGA RGB Video with Audio Cable Lead Converter Adapter is a versatile solution for connecting a modern HDMI device to a vintage VGA monitor or TV. With a HDMI 1.4 Standard Male connector on one end and a VGA/SVGA D-Sub Female connector on the other, this adapter allows for seamless conversion and transfer of video and audio signals. Perfect for retro gaming systems, older laptops, or any device that requires a VGA connection, this converter ensures a reliable and high-quality connection for a seamless viewing experience.
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UGREEN HDMI Cable 4K/60Hz HDMI 2.0 Cable for RTX 3080 PS4 Xbox HDMI Splitter HDMI Switch Aux Ethernet cable 4K 3D Cable HDMI
Aliexpress UK
HDMI to 3RCA Adapter -- This HDMI to 3RCA cable is used to signal transmit from a player to TV. It is also not possible to use the HDTV adapter to transfer this line to the TV. It works as a signal transmitter, not a signal converter.
eBay
UGREEN HDMI Cable 4K 2.0 Cable for Apple TV PS4 Splitter Switch Box HDMI to HDMI Cable 60Hz Video Audio Cabo Cord Cable HDMI 4K
Aliexpress UK
The Extron RGB-HDMI 300 A is a versatile scaler designed to convert and integrate stereo audio and RGB video signals seamlessly into HDMI output. Extron RGB-HDMI 300 A Stereo Audio to HDMI Scaler. High-quality scaler with precise video conversion.
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Mini HDMI cable 4K 60Hz HDMI 2.0 Mini HDMI to HDMI cable adapter Mini HDMI male to HDMI female cable Coupler Adapter
Aliexpress UK