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Best 8 Channel HDMI to Coax Modulators (November 2026): 10 picks from Thor Broadcast and kurtmark, from retro CRT gaming to multi-room QAM distribution.

The most common mistake in this category is buying the wrong kind of modulator. A small NTSC box that outputs on channel 3 or 4 feeds one old CRT television and nothing else. A digital QAM or ATSC encoder puts HDMI video on a proper channel that modern TVs and cable-style distribution can tune. Buy the first when you need the second and the signal never appears. Buy the second for a single retro console and you pay for features you cannot use. The Best 8 Channel HDMI to Coax Modulators depend on how many sources you need to send, which TVs must receive them, and whether those TVs tune analog channels or digital ones.
The short answer: the kurtmark HDMI to RF Modulator Kit suits anyone connecting one HDMI device to an older antenna-input TV with everything in the box, the Thor Broadcast H-HDMI-RF-PETIT suits a single source delivered as a digital QAM or ATSC channel, and the VQP HDM61 VHF Modulator suits retro gaming on a CRT with a fixed CH3/CH4 output. The rest of the list covers dual-input analog boxes, a single-channel digital encoder, and three Thor Broadcast units built for true multi-source distribution, including two with eight inputs.
TL;DR: top picks at a glance
- Best overall: the kurtmark HDMI to RF Modulator Kit, a complete plug-and-play kit with a 1.2 m HDMI cable, RG6 coax and power supply, outputting NTSC on CH3/CH4.
- Best for digital QAM/ATSC from one source: Thor Broadcast H-HDMI-RF-PETIT, a 9.6 oz unit that encodes up to 1080p with AC3 audio and is controlled from a PC.
- Best for retro CRT gaming: VQP HDM61 VHF Modulator, with fixed CH3 (61.25 MHz) and CH4 (67.25 MHz) output and 1080p to 480p input handling.
- Best for eight independent channels: Thor Broadcast 8-Channel HDMI and SDI, with 8 HDMI/SDI inputs mapped to 8 separate RF channels.
| # | Product | Best for | Output | Inputs | Weight |
|---|---|---|---|---|---|
| 1 | kurtmark HDMI to RF Modulator Kit | Complete CRT kit | NTSC CH3/CH4 | HDMI | Not listed |
| 2 | Thor Broadcast H-HDMI-RF-PETIT | Single digital channel | QAM/ATSC/DVB-T/ISDB-T | HDMI | 9.6 oz |
| 3 | VQP HDM61 VHF Modulator | Retro gaming | NTSC CH3/CH4 | HDMI | Not listed |
| 4 | ADRFClub HDMI/RCA UHF Modulator | Mixed HDMI and RCA | NTSC/PAL, VHF/UHF | HDMI or RCA | Not listed |
| 5 | SatLink ST-7000 | Digital single feed | ATSC or QAM (J.83B) | HDMI | 3.2 lb |
| 6 | RQG VHF UHF Modulator | Multi-TV analog | VHF/UHF, PAL/NTSC | HDMI or RCA | 13.4 oz |
| 7 | upxuntek CH3/CH4 Modulator | Antenna pass-through | NTSC CH3/CH4 | HDMI | 1.78 oz |
| 8 | Thor Broadcast 8-HDMI QAM Modulator | Eight HDMI sources | QAM/ATSC/ISDB-T | 8 HDMI | 9.4 lb |
| 9 | Thor Broadcast 8-Channel HDMI and SDI | Eight-channel headend | QAM/ATSC/DVB-T/ISDB-T | 8 HDMI or SDI | 9 lb |
| 10 | Thor Broadcast Rack-Mount QAM Modulator | Rack-based distribution | QAM/ATSC/DVB-T/ISDB-T | HDMI | 10 lb |

Pros:
Cons:
Best for: A buyer connecting a Fire TV Stick, Roku or console to a single older RF-input TV who wants one box with every cable included.
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What sets the kurtmark apart is the bundle. The upxuntek CH3/CH4 Modulator and VQP HDM61 VHF Modulator use the same CH3/CH4 approach, but only this kit lists a coax cable alongside the HDMI lead. That removes the most common first-day problem, which is finding an RG6 cable of the right length.
On the signal side, the listed 80 ± 5 dBµV output and PLL control point to a unit built for a short run into one television. It accepts HDMI 1.4 sources with HDCP 1.4, which covers streaming sticks, Apple TV, PS5, Xbox, Switch, PCs and DVD players. Compared with the ADRFClub HDMI/RCA UHF Modulator, it has fewer tuning options but also fewer settings to get wrong.
It is the wrong choice if you need a digital channel or more than one source. For a QAM or ATSC output from a single HDMI feed, the Thor Broadcast H-HDMI-RF-PETIT is the listed option that fits. For eight sources, jump to the Thor Broadcast 8-Channel HDMI and SDI.

Pros:
Cons:
Best for: A user sending one camera, receiver or player to several digital TVs over existing coax.
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The Thor Broadcast H-HDMI-RF-PETIT is the entry point to digital modulation in this list. It combines MPEG2 encoding with AC3 audio and an internal digital modulator, and you pick the RF channel yourself. That is a different job from the CH3/CH4 boxes ranked above it.
Against the SatLink ST-7000, which also targets ATSC or QAM from a single HDMI source, the Thor is the lighter and more fully described unit. The SatLink lists a 3.2 lb body, while the Thor weighs 9.6 oz and lists its encoder details.
It is the wrong choice for plug-and-play use with an old television, since the PC-based setup is unnecessary there. Pick the kurtmark HDMI to RF Modulator Kit for that. If you need several sources at once, step up to the Thor Broadcast 8-HDMI QAM Modulator.

Pros:
Cons:
Best for: A retro gamer connecting a modern console, handheld or PC to a CRT that only has an antenna input.
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The VQP HDM61 is the clearest fit for retro use in this list. Buyers report running low-resolution modes such as 640×480 from handheld PCs, which is exactly where a CH3/CH4 modulator makes sense. The fixed VHF frequencies keep configuration simple.
Compared with the kurtmark HDMI to RF Modulator Kit, it ranks lower because the accessory set is less clearly described and picture quality reports are inconsistent. If the image looks soft, setting the console to 480p is the most practical fix.
It is the wrong choice if you need to feed a UHF-only set or switch between NTSC and PAL. The ADRFClub HDMI/RCA UHF Modulator covers both. It also cannot take a composite source, which the RQG VHF UHF Modulator can.

Pros:
Cons:
Best for: A hobbyist feeding both HDMI and composite sources into a CRT or several rooms of analog TVs.
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The ADRFClub is the most flexible analog box here. With 136 channels across VHF and UHF, plus NTSC and PAL, it can dodge a channel that suffers interference, which a CH3/CH4 box cannot do. Buyers who live near a router or other RF noise often shift to a different channel for that reason.
The trade-off is a fiddly setup and thin documentation. Compared with the RQG VHF UHF Modulator, which also takes HDMI and RCA, the ADRFClub adds a digital channel readout, but both need patience.
It is the wrong choice for a first-time buyer who wants zero fiddling: the kurtmark HDMI to RF Modulator Kit is simpler. It is also not a digital QAM or ATSC product, so use the Thor Broadcast H-HDMI-RF-PETIT where digital channels are required.

Pros:
Cons:
Best for: An installer who needs one HDMI feed delivered as a digital channel on an in-building coax network.
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The SatLink ST-7000 targets the same job as the Thor H-HDMI-RF-PETIT, with less published detail. Where the Thor documents MPEG2 and AC3 handling, the SatLink states only 1080p delivery as ATSC or QAM, so you are choosing on trust more than specification.
It is the wrong choice if you need multiple channels, since it is listed with one. The Thor Broadcast 8-Channel HDMI and SDI is the listed answer there. If you only want to feed a CRT, the upxuntek CH3/CH4 Modulator is far smaller and simpler.

Pros:
Cons:
Best for: A user splitting one source across several analog TVs who needs to trim the output level.
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The RQG distinguishes itself with level adjustment. When one modulator feeds several TVs through a splitter, signal level matters, and the front-panel adjustment lets you compensate. The ADRFClub HDMI/RCA UHF Modulator offers similar input flexibility but has a channel display in its place.
Reliability reports make it a risk for permanent installs. It is the wrong choice for a long-term hospitality or signage setup, where one of the Thor digital units is better. For a casual single-TV setup, the upxuntek CH3/CH4 Modulator is smaller.

Pros:
Cons:
Best for: Someone who wants to keep an antenna connected to an older TV while adding an HDMI device.
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The upxuntek is the antenna-friendly option. Its RF pass-through is the feature that separates it from the kurtmark HDMI to RF Modulator Kit and the VQP HDM61 VHF Modulator, which list only an RF output.
It is the wrong choice if you want a coax cable in the box or PAL output. For the cable, choose the kurtmark kit. For PAL and UHF, choose the RQG VHF UHF Modulator.

Pros:
Cons:
Best for: A venue or building that needs several live HDMI feeds put onto its coax network.
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This Thor Broadcast unit is the closest match to the keyword for buyers who want eight HDMI inputs in one chassis. Its 1080p/60 input, MPEG2 video and AC3 audio match the other Thor digital modulators, but it adds the port count and closed-caption input.
Compared with the Thor Broadcast 8-Channel HDMI and SDI, it has fewer documented controls. Where that model describes individually selectable modulation per channel, this one says less about how its eight channels are configured.

Pros:
Cons:
Best for: A church, school or hotel that wants eight live sources on eight separate RF channels.
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This is the only listed product that delivers a true eight-channel hybrid design in the sense the keyword implies: eight inputs, eight independent outputs. Being able to mix modulation standards across channels, such as QAM on two and ATSC on three, is what makes it useful in a building with mixed TV types.
For smaller needs, a 4 channel QAM modulator is the usual step down in size, and for IP delivery a 4 channel IPTV encoder covers the networked side. Within this list, the Thor Broadcast 8-HDMI QAM Modulator is the simpler eight-port alternative if you do not need SDI.
It is the wrong choice for one TV or a gaming setup. Pick the kurtmark HDMI to RF Modulator Kit there.

Pros:
Cons:
Best for: An integrator filling a rack who values remote management over compactness.
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The rack-mount Thor Broadcast modulator is defined by its web management and stated latency. Neither of the other Thor units here lists those details so clearly, which matters when you maintain a system remotely.
Its weakness is the missing channel count. If you specifically need eight outputs, the Thor Broadcast 8-Channel HDMI and SDI documents them directly. For a small home install it is the wrong choice, and the Thor Broadcast H-HDMI-RF-PETIT does the digital job in a far smaller body.
The core trade-off is simplicity against capacity. Small analog boxes like the kurtmark HDMI to RF Modulator Kit are cheap in effort, but serve one TV and one source. Digital headend units like the Thor Broadcast 8-Channel HDMI and SDI serve many, but need planning.
Before choosing, check these project details:
Analog output suits old televisions. The VQP HDM61 VHF Modulator and upxuntek CH3/CH4 Modulator use fixed channels, while the ADRFClub HDMI/RCA UHF Modulator and RQG VHF UHF Modulator cover VHF and UHF.
Digital output suits modern TVs and shared coax networks. The Thor Broadcast H-HDMI-RF-PETIT and SatLink ST-7000 each put one feed on a QAM or ATSC channel, and the larger Thor units extend that to multiple outputs.
Most small modulators take one HDMI input. The ADRFClub and RQG add composite RCA, which helps if a VCR or older console is part of the setup.
For several sources, the Thor Broadcast 8-HDMI QAM Modulator has eight HDMI ports, and the Thor Broadcast 8-Channel HDMI and SDI adds SDI selection per channel. Buyers who outgrow eight channels may look at a 16 channel encoder for the source side.
Single-channel units are fine for one room. Once you want different sources on different TVs, you need separate RF channels, as on the Thor Broadcast 8-Channel HDMI and SDI.
The rack-mount Thor does not state its capacity, so confirm it before purchase. For a building that needs only a few outputs, a 4 channel QAM modulator class of product is a smaller target.
Small boxes run on 5V adapters, as listed on the kurtmark and upxuntek units. Larger Thor devices use North American 2-pin plugs and weigh around 9-10 lb.
Reliability varies. Buyers have reported failures on the ADRFClub and RQG after months of use, while the upxuntek lists a 1-year manufacturer warranty and the Thor H-HDMI-RF-PETIT lists a 1-year warranty.
It converts an HDMI video source into an RF signal that travels over coax cable to a TV. Analog units like the kurtmark HDMI to RF Modulator Kit output on CH3 or CH4. Digital units like the Thor Broadcast H-HDMI-RF-PETIT output QAM or ATSC channels.
The Thor Broadcast 8-Channel HDMI and SDI is listed with eight independent inputs and eight separate RF outputs. The Thor Broadcast 8-HDMI QAM Modulator has eight HDMI ports. The rest of the list is mostly single-source.
Yes, if the TV has a coax input. The VQP HDM61 VHF Modulator and upxuntek CH3/CH4 Modulator suit this, and buyers use 480p modes for best results. Set the TV to channel 3 or 4 to match the switch.
No. Both the kurtmark and upxuntek units convert HDMI to RF only. Neither reverses the signal.
Yes, through a coax splitter. The RQG VHF UHF Modulator has an adjustable output level that helps, and buyers have run several TVs from it. Digital units like the SatLink ST-7000 suit shared coax networks.
Analog units send an NTSC or PAL signal that old tuners read. Digital ones such as the Thor Broadcast Rack-Mount QAM Modulator encode video as QAM or ATSC. Choose based on what the receiving TV can tune.
Best 8 Channel HDMI to Coax Modulators for most home buyers start with kurtmark HDMI to RF Modulator Kit: it outputs NTSC on CH3/CH4, accepts 1080P to 480P input, and includes an HDMI cable, RG6 coax and power supply. Its main weakness is that it serves one source and one analog TV only.
For other uses, the Thor Broadcast H-HDMI-RF-PETIT suits digital QAM or ATSC delivery from one source, and the VQP HDM61 VHF Modulator suits retro gaming. The ADRFClub HDMI/RCA UHF Modulator and RQG VHF UHF Modulator fit mixed HDMI and composite sources, and the upxuntek CH3/CH4 Modulator is the pick for keeping an antenna connected.
For real multi-source work, the Thor Broadcast 8-Channel HDMI and SDI offers eight independent outputs, the Thor Broadcast 8-HDMI QAM Modulator gives eight HDMI ports, and the Thor Broadcast Rack-Mount QAM Modulator adds rack mounting and web control. The SatLink ST-7000 fits a single digital feed. If you are still undecided, count your sources and check whether your TVs tune analog or digital channels, then choose the smallest unit that covers both.