Long distance signal transmission can be carried out by the coaxial cable. Your PC/DVD/Set-top box with HDMI can play on old TV that without HDMI. 1 x HDMI To RF Converter. Output picture quality will be lower to RF analog signal(more like 480p).
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AU Australian CN China AC Power Electric Plug To EU Switzerland Italy Charging converter Plug Travel Adaptor Adapter Converter
Aliexpress UK
Use existing RF circuits in for general households. RF Frequency Range: 471.25MHz-885.25MHz. RF Output Impedance: 75Ω Unbalanced. 1 RF Modulator. Video Input Impedance: 75Ω. Audio Carrier Frequency: 4.5/5.5/6.0/6.5MHz.
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RCA to HDMI 1080P Converter Switch 4 in 1 out Composite AV to HDMI Scaler Switch converter with Remote 3 RCA AV in HDMI out
Aliexpress UK
Insert for rf cable and connect for rf output of the unit to for rf in the TV cable/antenna. Easily convert the interface you need into radio frequency for RF output, and modulate its interface to radio frequency high frequency output.
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HDMI-compatible to VGA Cable Converter Male To Famale Converter Adapter 3.5mm Jack Audio HD 1080P For PC Laptop Tablet
Aliexpress UK
New and unused, although has been sitting in storage for 20 years so has some scuffs paint/label.
eBay
HDMI-compatible To AV RCA Adapter Converter MINI Box RCA AV CVSB LR Video Composite AV Scaler Converter For PC HDTV Projector
Aliexpress UK
HDMI RF signal transmitter - HDMI coaxial output, long-distance signal transmission can be used in different rooms through coaxial cable. RF Coaxial Converter - Outputs only analog signals, image quality will be lower than RF analog signals (more like 480p); not applicable to ATSC format!
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SCART to HDMI Converter SCART to HDMI Adapter Output Audio Converter Adapter Audio Head For Crt TV Vhs Video Recorder HD 1080
Aliexpress UK
Connector A: SO239 UHF female, Nickel plating. 1x SO239 - BNC Adapter Supplied. Connector B: BNC male, Nickel plating. This item will be fully inspected prior to dispatch. We only accept cash on collection.
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4K 60Hz Type C to HDMI Adapter USB 3.1 HUB HDTV Converter Cable for iPhone 15 TV Converter for PC MacBook iPad Samsung Laptop
Aliexpress UK
Mini HD video converter, forRCA AVfor CVSB tofor RF video adapter, supportsfor RF 67.25MHz and 61.25MHz, and is a zoom AV tofor RF TV switcher. AV to RF signal converter converts video or audio signals into RF composite video and audio signals, and supports DVI auxiliary signals.
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4K 30/60Hz USB C to HDMI Cable Type C Adapter HDTV Converter Cable For iPhone 15 TV Converter MacBook Air iPad Samsung laptop
Aliexpress UK
New and unused, although has been sitting in storage for 20 years so has some scuffs paint/label.
eBay
Serial Port RS232 To WiFi Device Server Converter Elfin-EW10 EW10A Support TCP/IP Telnet Modbus IOT Data Converter Transfer
Aliexpress UK