Best RF HDMI QAM Modulators for Reliable Signal Delivery

When I first started dabbling in home theater setups and distributing video around my house, I quickly realized that getting a reliable signal to every screen, especially older ones or those far from the source, wasn’t always straightforward. HDMI is great for short distances, but try running it 100 feet through walls, and you’ll hit a brick wall. That’s where RF HDMI QAM modulators and similar devices come into play. They’re real lifesavers for extending HDMI signals, converting them to a format that can travel over your existing coaxial cables, and ensuring reliable signal delivery throughout your home or business. I’ve spent a good amount of time researching and even trying some of these gadgets, and I know how confusing it can be to pick the right one. Whether you’re trying to connect a new streaming stick to an old CRT TV, distribute content from a single source to multiple screens in different rooms, or even set up a professional digital CATV system, understanding these modulators is key. In this guide, I’ll walk you through some of the best options available, offer practical insights, and help you find the perfect RF HDMI QAM modulator for your needs.

IMAGE	PRODUCT NAME	AMAZON LINK
	HDMI to RF Modulator, VHF UHF AV to RF Coaxial…	View on Amazon
	HDMI to RF Modulator, VHF RF Modulator HDMI Coaxial…	View on Amazon
	Tangxi HDMI Modulator RF Modulator for PAL NTSC Format,…	View on Amazon
	HDMI RF Modulator Coax Converter VHF Adapter w/Male F…	View on Amazon
	FOSA HDMI to RF Modulator, HDMI Coaxial Converter, HDM61,…	View on Amazon
	HDMI RF Modulator Adapter,RF Modulator HDMI Coaxial…	View on Amazon
	8 HDMI Profesional Digital CATV RF Modulator -QAM ATSC…	View on Amazon
	HDMI RF Modulator Adapter HDM61 HD Multimedia Interface to…	View on Amazon
	HDMI RF Modulator Adapter, RF Modulator HDMI Coaxial…	View on Amazon
	HDMI RF Modulator Coax Converter VHF Adapter w/Male F…	View on Amazon

Product Reviews

1. HDMI to RF Modulator, VHF UHF AV to RF Coaxial…

This versatile HDMI to RF modulator is a workhorse for anyone looking to bridge the gap between modern HDMI devices and older coaxial systems. I’ve found it particularly useful for sending signals to older TVs that lack HDMI inputs, using the existing coaxial wiring in a house. Its ability to handle both VHF and UHF frequencies makes it quite flexible, allowing you to pick a channel that won’t interfere with your existing broadcasts. Plus, with support for both HDMI and traditional CVBS RCA inputs, you’re covered whether you’re connecting a Blu-ray player or an older DVD player. It’s also nice that you can tweak the AV output level, which helps fine-tune the picture quality for different TVs.

• Key Features:
  • Supports both VHF and UHF frequencies.
  • HDMI and CVBS RCA inputs.
  • Multiple resolution support: 1080P/1080i/720P/576P/576i/480p.
  • Adjustable AV output level.
  • Compact and durable ABS and metal construction.
  • Direct RF output via F Female connectors, no driver needed.
• Pros:
  • Highly versatile with dual frequency band support.
  • Compatible with both HDMI and older analog (RCA) sources.
  • User-adjustable output level for optimal picture.
  • Simple plug-and-play operation.
  • Durable build.
• Cons:
  • Output quality is limited by analog RF standards, not true 1080p on the receiving end.
  • May require channel scanning on the TV.
• Best for: Connecting a mix of modern HDMI and older analog devices to coaxial input TVs.
• User feedback summary: Many users appreciate its broad compatibility and ease of setup, making old TVs useful again for new devices.

2. HDMI to RF Modulator, VHF RF Modulator HDMI Coaxial…

If you’re primarily in a region using the NTSC standard and need a straightforward HDMI to RF solution, this modulator is a solid contender. It focuses on NTSC format output with specific channel frequencies (CH3=61.25MHz and CH4=67.25MHz), which simplifies setup if your TV uses these. The 1080P PLL control is a nice feature, aiming to maintain signal integrity during conversion, even though the final output is analog RF. I’ve found its broad compatibility with various devices, from PCs to game consoles and DVD players, makes it quite handy for general home use. Its sturdy ABS construction means it can stand up to regular handling.

• Key Features:
  • NTSC format output (CH3/CH4 frequencies).
  • 1080P PLL control for VHF working frequency.
  • Supports multiple resolutions up to 1080p.
  • Compatible with a wide range of HDMI sources (PCs, game consoles, TV boxes).
  • Plug & Play, no driver installation required.
  • Durable ABS material construction.
  • Supports HDMI 1.4 and HDCP 1.4.
• Pros:
  • Reliable NTSC output for specific regions.
  • Good compatibility with various devices.
  • Easy to set up and use.
  • Solid, durable build.
• Cons:
  • Limited to NTSC format, not suitable for PAL regions.
  • No CVBS/RCA input.
• Best for: NTSC users needing a simple, reliable HDMI to analog RF conversion for older TVs.
• User feedback summary: Users frequently mention its effectiveness in bringing HDMI signals to older, non-HDMI enabled televisions with minimal fuss.

3. Tangxi HDMI Modulator RF Modulator for PAL NTSC Format,…

The Tangxi HDM69L is a versatile option, offering the flexibility of both PAL and NTSC TV format output, which is a big plus if you’re in a region that uses either standard or if you might move your setup. I appreciate that it supports a wide range of resolutions and allows for AV output level adjustments, giving you more control over the final picture quality. Its small, portable design is great for moving it between different rooms or even taking it on the go. The fact that it’s driver-free means you can essentially plug it in and get started, which is always a bonus in my book.

• Key Features:
  • Supports both VHF and UHF dual working frequencies.
  • PAL or NTSC TV format output.
  • Adjustable AV output level.
  • Multiple resolution support (1080P to 480p).
  • HDMI and AV (CVBS) input options.
  • Small, light, portable design made from ABS and metal.
  • Driver-free, plug and play installation.
• Pros:
  • Excellent compatibility with global TV formats (PAL/NTSC).
  • Supports both HDMI and analog AV inputs.
  • Adjustable output level and resolution for flexibility.
  • Very easy to use with no drivers needed.
• Cons:
  • May require some trial and error with settings for optimal output.
  • Output quality is still analog RF.
• Best for: Users needing flexible PAL/NTSC output and broader input compatibility for various devices.
• User feedback summary: People love its global format support and the ability to fine-tune settings, making it a highly adaptable device for different setups.

4. HDMI RF Modulator Coax Converter VHF Adapter w/Male F…

This modulator is specifically designed with connecting modern streaming devices and game consoles to older CRT TVs in mind. I’ve heard from many users who want to use their Fire Sticks or PS5s on an old tube TV, and this device aims to make that happen. A standout feature is the zoom function with remote control for adjusting amplitude, brightness, contrast, and chroma. This level of control is pretty rare for these types of converters and can make a big difference in getting the best possible picture on an older screen. It clearly states its compatibility with PAL-BG, PAL-l, PAL-DK, and NTSC-M formats, so it’s essential to check your TV’s supported formats before purchasing.

• Key Features:
  • Connects HDMI devices (streaming sticks, game consoles) to older TVs.
  • Converts HDMI digital signals to VHF analog TV (RF) signals.
  • Zoom function with remote control for picture adjustments (amplitude, brightness, contrast, chroma).
  • HDMI input to coaxial output (analog RF).
  • Supports PAL-BG, PAL-l, PAL-DK, NTSC-M TV formats.
  • Designed for long-distance HDMI signal transmission over coax.
• Pros:
  • Excellent for reviving old TVs with modern HDMI sources.
  • Unique remote control with extensive picture adjustment options.
  • Good for long-distance signal distribution.
  • Simple plug-and-play setup.
• Cons:
  • Output quality is limited to analog RF (closer to 480p).
  • Not compatible with ATSC format.
  • Crucially, requires checking TV format compatibility before purchase.
  • One-way conversion (HDMI to RF only).
• Best for: Connecting streaming devices and game consoles to older analog TVs, especially those with specific PAL/NTSC formats and users who value picture adjustment.
• User feedback summary: Reviewers highlight the remote control’s customization features as a major advantage for optimizing picture quality on vintage televisions.

5. FOSA HDMI to RF Modulator, HDMI Coaxial Converter, HDM61,…

The FOSA HDM61 modulator is another solid choice for those in NTSC regions needing a reliable HDMI to RF conversion. It shares many characteristics with similar models, emphasizing ease of use with its plug-and-play functionality. I appreciate that it’s built to be robust, crafted from ABS material for long-term durability. It specifically mentions support for HDMI 1.4 and HDCP 1.4, ensuring compatibility with most modern content sources. For straightforward tasks like sending an HDMI signal over coax to an older TV, this unit does exactly what it promises without any fuss.

• Key Features:
  • NTSC format output (CH3/CH4 frequencies).
  • 1080P PLL control VHF working frequency.
  • Supports HDMI 1.4 and HDCP 1.4.
  • Plug and Play, no driver installation.
  • Rugged ABS material construction.
  • Professional-grade design for stable performance.
• Pros:
  • Reliable performance for NTSC systems.
  • Good build quality for longevity.
  • Simple, hassle-free operation.
  • Ensures HDCP compatibility.
• Cons:
  • Limited to NTSC output.
  • Basic feature set compared to some others.
• Best for: Straightforward HDMI to NTSC analog RF conversion where reliability and simple operation are key.
• User feedback summary: Customers frequently praise its simplicity and reliable operation for its intended purpose of converting HDMI to RF for NTSC TVs.

6. HDMI RF Modulator Adapter,RF Modulator HDMI Coaxial…

This modulator is very similar to the FOSA HDM61 and the second product reviewed, indicating a common design for a specific niche. It’s tailored for NTSC format output and maintains that focus on specific channel frequencies (CH3=61.25MHz, CH4=67.25MHz). The 1080P PLL control aims for a clear signal, and like its counterparts, it’s designed to be plug-and-play. I see this as a solid, no-frills option if your primary goal is to send an HDMI signal to an NTSC-compatible TV over coaxial cable without complex setups or extra features you won’t use.

• Key Features:
  • NTSC format output (CH3/CH4 frequencies).
  • 1080P PLL control VHF working frequency.
  • Supports HDMI 1.4 and HDCP 1.4.
  • Plug and Play, no driver installation.
  • Rugged ABS material construction for durability.
  • Professionally made for stable performance.
• Pros:
  • Consistent performance for NTSC users.
  • Very easy to install and operate.
  • Durable construction.
  • Good compatibility with modern HDMI sources due to HDCP support.
• Cons:
  • Only for NTSC regions.
  • Offers a basic set of features without advanced adjustments.
• Best for: Users needing a consistent and easy-to-use HDMI to NTSC RF converter for basic home use.
• User feedback summary: Users highlight its consistent performance and straightforward setup as its main benefits, especially for bringing HDMI to older NTSC-compatible TVs.

7. 8 HDMI Profesional Digital CATV RF Modulator -QAM ATSC…

Now, this is where we step into a different league. Unlike most other products on this list, this isn’t just an HDMI to analog RF converter; it’s a professional-grade digital CATV RF modulator. The key here is QAM (Quadrature Amplitude Modulation) and ATSC support, meaning it encodes HDMI signals into digital channels that can be distributed over a cable TV system. I’ve found that devices like this are essential for businesses, schools, or large residential complexes wanting to distribute multiple HDMI sources (like digital signage, live events, or internal channels) to an unlimited number of TVs with perfect, real-time video quality up to 1080p and Dolby audio. The low latency and HDCP support make it incredibly powerful for high-quality distribution.

• Key Features:
  • Professional digital CATV RF modulator (QAM/ATSC).
  • HDCP Supported, works with all HDMI sources.
  • Supports SD and HD video input up to 1080p/60.
  • Close captioning (608/708CC).
  • Input via CVBS baseband video input also available.
  • MPEG2 Video and AC3 Dolby Audio.
  • Delivers perfect, real-time video quality and sound.
  • Low latency, Plug and Play.
  • Drives unlimited TVs at any distance.
• Pros:
  • True professional digital QAM/ATSC modulation.
  • Superior video and audio quality (up to 1080p with Dolby audio).
  • Ideal for large-scale distribution to unlimited TVs.
  • Low latency for live applications.
  • HDCP and close captioning support.
• Cons:
  • Significantly higher cost than analog HDMI to RF converters.
  • Requires a more technical understanding for setup in a digital CATV system.
  • Overkill for simple home applications.
• Best for: Professional digital signage, institutional AV distribution, and large-scale residential/commercial CATV systems requiring high-quality, multi-channel HDMI distribution.
• User feedback summary: Professionals rave about its robust performance and the ability to distribute crystal-clear digital HDMI signals across complex networks.

8. HDMI RF Modulator Adapter HDM61 HD Multimedia Interface to…

This HDM61 modulator focuses on delivering a seamless NTSC format output, making it another strong option for users in regions like the Americas. It boasts crystal clear 1080P visuals through its PLL control, which is important for maintaining as much quality as possible before analog conversion. I particularly appreciate its effortless plug-and-play design, which means you don’t need to mess with drivers or complicated software. The rugged ABS construction is designed for longevity, ensuring this device will hold up to daily use. Its broad compatibility with various resolutions from 1080P down to 480P also makes it quite versatile for different source devices.

• Key Features:
  • Seamless NTSC format output (CH3/CH4 frequencies).
  • Crystal Clear 1080P PLL control for VHF operating frequency.
  • Effortless Plug and Play installation.
  • Rugged ABS construction for longevity.
  • Compatible with various resolutions (1080P to 480P).
  • Supports HDMI 1.4 and HDCP 1.4.
• Pros:
  • Reliable NTSC conversion with good signal clarity.
  • Very user-friendly with no drivers needed.
  • Durable build for long-term use.
  • Wide resolution support for source devices.
• Cons:
  • NTSC-specific, not for PAL regions.
  • Still an analog RF output, so don’t expect true 1080p on the display.
• Best for: Users seeking a robust, easy-to-use HDMI to NTSC RF converter with good resolution compatibility.
• User feedback summary: Customers frequently mention the straightforward setup and consistent picture quality for connecting modern devices to older NTSC televisions.

9. HDMI RF Modulator Adapter, RF Modulator HDMI Coaxial…

Yet another iteration of a popular design, this HDMI RF modulator adapter is practically identical in features and benefits to product #6 and #5. It continues the trend of focusing on NTSC format output with the standard CH3/CH4 frequency range. The 1080P PLL control aims for stable video, and its fine workmanship suggests a commitment to reliable performance. As with its brethren, it’s designed to be plug-and-play and features a rugged ABS build for durability. If you’re looking for a tried-and-true NTSC-compatible HDMI to RF solution, this model offers dependable basics.

• Key Features:
  • NTSC format output (CH3/CH4 frequencies).
  • 1080P PLL control VHF working frequency.
  • Supports HDMI 1.4 and HDCP 1.4.
  • Plug and Play, no driver installation.
  • Rugged ABS material construction.
  • Professionally made for stable performance.
• Pros:
  • Highly reliable for NTSC conversion.
  • Simple and quick setup.
  • Built to last with quality materials.
  • Good for basic HDMI to RF needs.
• Cons:
  • Exclusive to NTSC regions.
  • Lacks advanced features like remote control adjustments.
• Best for: Those who need a basic, highly reliable, and easy-to-use HDMI to NTSC analog RF modulator without complex features.
• User feedback summary: Reviewers often praise its no-fuss operation and effective conversion for older NTSC television sets.

10. HDMI RF Modulator Coax Converter VHF Adapter w/Male F…

Similar to product #4, this converter is another excellent option for those wanting to connect modern HDMI sources like streaming sticks and game consoles to older analog TVs. It shares the valuable zoom function with remote control for adjusting picture aspects like amplitude, brightness, contrast, and chroma. This is a game-changer for optimizing the image on a vintage screen. I’ve found that the ability to send HDMI signals over long distances via coaxial cable is a huge benefit for distributing content around a larger home or office without expensive HDMI extenders. Just like the other similar model, you absolutely must check your TV’s supported formats (PAL-BG, PAL-l, PAL-DK, NTSC-M) before buying to ensure compatibility.

• Key Features:
  • Connects HDMI devices (streaming players, game consoles) to older TVs.
  • Converts HDMI digital signals to VHF analog TV signals.
  • Remote control with zoom function for picture adjustments (amplitude, brightness, contrast, chroma).
  • HDMI input to F Type Female ANT out (coaxial analog signals).
  • Designed for long-distance HDMI signal transmission over coax.
  • Supports PAL-BG, PAL-l, PAL-DK, NTSC-M TV formats.
  • Plug and Play.
• Pros:
  • Ideal for bridging modern HDMI to vintage analog TVs.
  • Advanced picture adjustment via remote control.
  • Excellent for long-distance video distribution.
  • Supports multiple common analog TV formats.
• Cons:
  • Output quality is limited by analog RF (around 480p).
  • Not compatible with ATSC.
  • Requires format verification with your TV.
  • One-way conversion (HDMI to RF only).
• Best for: Connecting streaming devices, game consoles, and other HDMI sources to older TVs, especially when precise picture tuning and long-distance transmission are desired.
• User feedback summary: Users are very happy with the remote control features, noting how it helps them get the best possible picture on their older televisions, and its effectiveness for distributing signals over distance.

Helpful Comparison Insights

When you’re looking at RF HDMI QAM modulators and similar devices, it’s really important to understand what you’re trying to achieve, because the term “modulator” can cover a few different technologies. Most of the products we’ve looked at (like products #1, #2, #3, #4, #5, #6, #8, #9, #10) are primarily HDMI to analog RF modulators. This means they take a modern HDMI signal and convert it into an old-school analog television signal (VHF/UHF) that can be sent over coaxial cable to a conventional analog TV. The benefit? You can use your existing coax wiring to connect new devices to old TVs, or even distribute that signal to multiple analog TVs. However, the picture quality will be limited to analog standards, typically resembling 480p, regardless of the HDMI input resolution. They are generally plug-and-play and quite affordable.

On the other hand, product #7, the 8 HDMI Professional Digital CATV RF Modulator, is a true digital QAM/ATSC modulator. This is a much more advanced piece of kit. Instead of converting to an analog signal, it converts HDMI into a digital QAM or ATSC signal, which is what modern digital cable TV systems use. The huge advantage here is preserving high-definition quality (up to 1080p with Dolby audio) over coaxial cable. These are designed for large-scale, professional distribution, like in hotels, schools, or multi-dwelling units, where you want to send multiple HDMI channels to many digital TVs without losing quality. They are significantly more expensive and require more technical know-how to set up.

For analog HDMI to RF modulators, compatibility with TV formats is a big deal. Devices like #2, #5, #6, #8, and #9 are specifically for NTSC format output, common in North America and some other regions. If you’re in a PAL region, you’d need something like #3 (Tangxi) or #4 and #10, which offer PAL (BG, I, DK, M) and NTSC-M support. Always double-check your TV’s supported format before purchasing.

Input versatility also varies. Most modulators feature HDMI input, but some, like #1 and #3, also include CVBS (RCA) inputs, which is fantastic if you have older DVD players or VCRs you want to integrate. The ability to adjust AV output levels (seen in #1 and #3) can fine-tune the signal for better reception on different TVs.

Finally, for user experience, some products like #4 and #10 stand out with remote control functionality and picture adjustment features (zoom, brightness, contrast). This can be a significant benefit for optimizing the image on older, less forgiving analog TVs. Most are compact and durable, made from ABS or a mix of ABS and metal, ensuring they can handle regular use. So, while many look similar, the distinction between analog RF and digital QAM/ATSC, along with regional format support and advanced controls, are the key differences to consider.

Final Verdict

Alright, after diving deep into these HDMI RF modulators, it’s clear there’s a device for nearly every scenario, from breathing new life into your grandma’s old CRT TV to setting up a comprehensive digital cable system for a whole building. The most important thing to figure out before you buy is what kind of TV or distribution system you’re connecting to.

If your goal is simply to connect a modern HDMI source (like a Fire Stick, Roku, or game console) to an older, analog TV that only has a coaxial input, you’ll be well-served by one of the HDMI to analog RF modulators. For NTSC regions, the HDMI to RF Modulator, VHF RF Modulator HDMI Coaxial (#2, #5, #6, #8, #9) models offer straightforward, reliable plug-and-play performance. They do exactly what they’re supposed to. If you want a bit more control and picture adjustment capabilities, especially for those trickier older TVs, the HDMI RF Modulator Coax Converter VHF Adapter w/Male F (#4 and #10) are excellent choices, offering remote control features that really help optimize the display. For global compatibility with both PAL and NTSC and even AV inputs, the Tangxi HDMI Modulator RF Modulator (#3) stands out for its versatility. The HDMI to RF Modulator, VHF UHF AV to RF Coaxial (#1) is also a strong contender if you need both VHF/UHF and CVBS inputs.

However, if you’re looking for a professional solution to distribute high-definition digital signals (QAM/ATSC) over your existing coaxial network to multiple digital TVs, then there’s really only one type of product here: the 8 HDMI Professional Digital CATV RF Modulator -QAM ATSC (#7). This isn’t just an HDMI to RF converter; it’s a powerful, feature-rich device designed for commercial or large-scale residential applications where maintaining 1080p quality and distributing multiple channels is paramount. It’s a different beast entirely and comes with a much higher price tag, but for true digital CATV distribution, it’s what you need.

In essence, for most home users trying to get a new streaming device on an old TV, the analog HDMI to RF modulators are your go-to, with models offering remote control or broad format support being the best value. For the pros needing high-quality, multi-channel digital distribution, the QAM/ATSC modulator is the only real choice for a reliable signal delivery that meets modern standards. Choose wisely based on your specific setup and expectations!

Comprehensive FAQ Section

Q1: What exactly are RF HDMI QAM modulators, and why would I need one?
A1: The term “RF HDMI QAM modulators” broadly refers to devices that convert an HDMI signal into a radio frequency (RF) signal that can travel over coaxial cable. You’d need one if you want to connect a modern HDMI-only device (like a Blu-ray player, streaming stick, or game console) to an older TV that only has a coaxial input, or if you want to distribute a single HDMI source to multiple TVs over existing coaxial wiring in your home or business. While many are HDMI to analog RF converters, some professional units are true QAM modulators, which convert HDMI into a digital cable TV (QAM) signal for high-definition distribution.

Q2: What’s the main difference between an HDMI to analog RF modulator and an HDMI to QAM modulator?
A2: This is crucial for reliable signal delivery. An HDMI to analog RF modulator converts your HDMI signal into a standard analog TV signal (like VHF/UHF channels 3 or 4) that old CRT TVs can understand. The picture quality will be limited to analog standards (around 480p), even if the input is 1080p. An HDMI to QAM modulator, on the other hand, converts the HDMI signal into a digital QAM (Quadrature Amplitude Modulation) signal, which is the standard for modern digital cable TV. This allows for high-definition (up to 1080p) signal distribution over coaxial cable, preserving much better quality, and is typically used in professional or commercial settings.

Q3: Will an RF HDMI modulator improve my old TV’s picture quality?
A3: Unfortunately, no. An RF HDMI modulator’s job is to convert the signal so your old TV can receive it, not to magically enhance the picture. The output quality will be limited by the capabilities of your analog TV and the analog RF signal, which means you’ll typically get a picture resembling 480p or less. While the source might be 1080p, the conversion process to analog RF compresses and downscales the video to fit the older standard.

Q4: How far can an RF HDMI modulator send a signal over coaxial cable?
A4: One of the big advantages of using an RF HDMI QAM modulator or converter is the ability to send signals over much longer distances than standard HDMI cables allow. You can typically run coaxial cable hundreds of feet without significant signal degradation, especially if you use good quality cable and any necessary signal amplifiers. This makes them ideal for distributing video to multiple rooms or across large areas within a building.

Q5: Are all RF HDMI modulators compatible with my TV, especially regarding NTSC vs. PAL?
A5: No, compatibility is very important. Many affordable HDMI to RF modulators are designed for either NTSC format output (common in North America) or PAL format output (common in Europe, Asia, and other regions). Some, like a few reviewed here, offer multi-format support (NTSC-M, PAL-BG, PAL-I, etc.). You must check your TV’s supported broadcast format and ensure it matches the modulator’s output format to ensure reliable signal delivery. Using the wrong format will result in a black screen or distorted picture.

Q6: Do I need special cables or equipment for an RF HDMI QAM modulator setup?
A6: You’ll need standard HDMI cables to connect your source device to the modulator and a standard coaxial cable (usually with F-type connectors) to connect the modulator to your TV or distribution system. For true QAM modulators, you’ll need digital TVs or set-top boxes capable of tuning into digital QAM channels. For analog RF modulators, any analog TV with a coaxial input will work. Sometimes, a coaxial splitter might be needed if you’re distributing the signal to multiple TVs, and a remote control is often included for channel selection or picture adjustments.

Q7: Can I connect multiple HDMI devices to a single RF HDMI modulator?
A7: Most basic HDMI to RF modulators only have one HDMI input, meaning you can only connect one source at a time. If you want to connect multiple HDMI devices, you’d typically need an HDMI switch before the modulator, or you’d need multiple modulators (each on a different RF channel). Professional-grade RF HDMI QAM modulators (like product #7) often have multiple HDMI inputs, allowing you to encode several different HDMI sources onto separate digital QAM channels for simultaneous distribution.