Our 4 ch H-4ADHD-QAM-IPLL worked on the Comcast system as an inserted channel.
We have simple GUI instructions on how to set it up, we can percent it everything before the shipping, so it would be just plugged and play.
We have also other similar modulators for 1,2,8 and 12channels.
We have great flexible products and  technical support
Please check those units for your reference
2 HDMI Modulator
https://thorbroadcast.com/product/2-hdmi-ypbpr-hd-digital-tv-modulator-qam-atsc-dvb-t-8230.html
8 HDMI/SDI  modulator
https://thorbroadcast.com/product/8-channel-hdmi-and-sdi-clear-catv-rf-modulator-qam-8230.html
12 HDMI modulator
https://thorbroadcast.com/product/catv-rf-modulator-hdmi-multiplexer.html/37

Please review the following options:

1) H-4ADHD-QAM-IPLL: 4-channel HDMI QAM modulator/IP Encoder with QAM
latency around 300ms and IP latency of approximately 800ms.


2) H-4SDI-QAM-IPLL: 4-channel SDI QAM modulator/IP Encoder with QAM
latency around 300ms and IP latency of approximately 800ms.

https://thorbroadcast.com/product/1-4-sdi-to-qam-modulators-and-iptv-streaming-encoders.html/0

3) If latency is not a concern, I suggest the H-THUNDER-8, an
8-channel QAM modulator with latency of about 500ms.

https://thorbroadcast.com/product/1-4-or-8-hdmi-digital-rf-encoder-modulator-8230.html/239


4) Here is the link for the 16 or 24-channel IP encoder with a latency of 800ms.
https://thorbroadcast.com/product/4-8-16-24-hdmi-iptv-streaming-8230.html/215
https://thorbroadcast.com/product/4-8-16-24-hdmi-iptv-streaming-8230.html/216

this is link to our IPTV STB's
https://thorbroadcast.com/product/compact-ip-decoder-set-top-box.html

ust to clarify, the H-IPRF-QAM-32CH will accept the H.264 stream and pass it to the RF QAM. However, most TVs will not support this because MPEG4 (H.264) is not a US CATV RF standard; most TVs require MPEG2.

If you need to transcode just 4 streams, the easiest way would be to decode those streams to HDMI format and use a 4-channel modulator. You can decode IP using the H-STB-IP, and for the 4-channel modulator, you can use the H-THUNDER-4.

https://thorbroadcast.com/product/compact-ip-decoder-set-top-box.html

H-THUNDER-4

https://thorbroadcast.com/product/hdmi-modulator-qam-rf-coax-output-full-hd-8230.html/238

Based on your description, this is a very typical broadcast distribution architecture and there is a straightforward way to achieve it.

At the central distribution point, you can use our
Thor Broadcast H-4ADHD-ATSC-IPLL encoder.  - https://thorbroadcast.com/product/4-hdmi-component-hd-to-coax-and-iptv-hd-8230.html/22

This unit accepts four HDMI program sources and multiplexes them into a single MPTS (Multi-Program Transport Stream) containing your four virtual channels, for example:

• 16.1

• 16.2

• 16.3

• 16.4

The encoder then sends this MPTS over IP to each transmitter location in your network.

Since each of your remote transmitter sites has a public static IP address, the encoder can simply transmit the stream using UDP unicast to all of the transmitter sites simultaneously.

Remote Transmitter Sites

At each transmitter location you would install our:

Thor Broadcast H-IP-ASI-B-V3  -  https://thorbroadcast.com/product/asi-to-ip-and-ip-to-asi-converted-with-decoding-8230.html

This unit receives the IP MPTS stream from the network and converts it back into ASI format, which can then be fed directly into the ASI input of your ATSC modulator.

The ATSC modulator then broadcasts the multiplex as RF with the four virtual channels.

System Architecture

Central Headend

4 Program Sources (HDMI)
→ H-4ADHD-ATSC-IPLL Encoder
→ MPTS over IP

Network Distribution

Internet / IP network
UDP Unicast to multiple transmitter locations

Remote Transmitter Site

IP Stream
→ H-IP-ASI-B-V3 (IP → ASI Converter)
→ ASI Output
→ ATSC Modulator
→ RF Broadcast (Channel 16 with subchannels 16.1 – 16.4)

Advantages of this Architecture

• One central encoder feeds all transmitter locations
• Very efficient IP distribution over the internet
• Each transmitter receives the same synchronized transport stream
• Fully compatible with ASI input on your ATSC modulators

Please let me know if this would work for you.

For 7 sites, you would need:

• 7 pcs H-4ATSC-ATSC-IPLL

• 7 pcs H-ASI-IP-B-V3

1. My modulator indicates that it accepts UDP unicast. Does your 4-ADHD send UDP unicast?
Yes. The H-4ADHD can output UDP unicast streams.

2. Can the 4-ADHD directly deliver 4 programs to my modulator as a one-to-one peer connection?
Yes. The unit can send either:

• UDP Unicast streams (one program per stream), or

• UDP Multicast MPTS, which contains all four transport streams in a single multiplex.

This allows flexibility depending on how your modulator expects to receive the streams.

3. Does the 4-ADHD allow both the ASI output and the Unicast IP output to be active at the same time?
Yes. Both ASI output and IP output can operate simultaneously.

4. I have a mix of ASI-only modulators that may require a unicast-to-ASI decoder.

That is correct. For modulators that only accept ASI input, you would use our IP-to-ASI converter to convert the IP stream back to ASI.

5. Pricing

Current pricing is as follows:

• H-4ADHD-QAM-IPLL (4-Channel Encoder / IP Output) – $3,895

• H-ASI-IP-B-V3 (ASI ↔ IP Converter / Decoder) – $2,995 - https://thorbroadcast.com/product/asi-to-ip-and-ip-to-asi-converted-with-decoding-8230.html

Your current system distributes television signals through a coaxial cable network to approximately 144 TVs throughout the vessel. The system was originally installed around 2012 and uses older analog modulators connected to DIRECTV receivers.

Over time, the system has developed issues such as:

• Analog picture degradation (ghosting and noise)

• Aging equipment

• Limited flexibility for adding new sources such as cameras or additional channels

Moving to digital QAM distribution will significantly improve reliability and picture quality while allowing the system to expand easily.

Recommended Core Solution

We discussed using the Thor Broadcast Thunder-8 HDMI QAM Modulator, which accepts 8 HDMI inputs and converts them into 8 digital QAM channels distributed over coax.

Product Link:
https://thorbroadcast.com/product/8-channel-hdmi-rf-modulator-atsc-or-qam-8230.html

Multiple modulators can be combined to create larger channel systems such as:

• 16 channels (2 units)

• 24 channels (3 units)

• 32+ channels if required

Each unit operates independently and can be easily combined using standard RF combiners.

Source Compatibility

The Thunder-8 modulator works with any HDMI source, including:

• DIRECTV receivers

• Satellite receivers

• Media players

• Computers

• Digital signage players

• Other HDMI devices

The system encodes video using MPEG-2 QAM, which provides maximum compatibility with televisions used in United States, Canada, and Mexico.

Existing RF Network Compatibility

Since your vessel already has a coax distribution network with amplifiers and splitters, there is a strong possibility that the new system can be installed with minimal changes.

In many cases the upgrade process is simply:

1. Remove the old analog modulators

2. Connect the digital QAM modulators

3. Rescan the TVs for digital channels

Digital QAM typically requires less RF power than analog, so existing amplifiers usually work without modification.

Older Television Compatibility

Some televisions onboard may be older analog or international models.

If a TV does not properly decode digital QAM, an external QAM set-top box may be used.

Example Decoder:
https://thorbroadcast.com/product/hdmi-qam-set-top-box-decoder-8230.html

These boxes convert QAM RF channels into HDMI output, allowing older TVs to continue operating.

Camera System Integration

You mentioned the vessel also uses a mix of IP cameras and analog cameras that may need to appear as channels on the TV system.

IP Cameras

IP camera streams (H.264) can be converted to HDMI using IP decoders.

Example IP Decoder:
https://thorbroadcast.com/product/iptv-decoder-set-top-box-8230.html

These decoders output HDMI, which can then be connected to the modulator to create a camera channel.

Analog Cameras

Analog cameras can also be added using modulators that support composite video input.

Example Analog + HDMI Modulator:
https://thorbroadcast.com/product/4-channel-hdmi-av-rf-modulator-8230.html

This allows legacy cameras to remain part of the system.

RF Combining and Distribution

Multiple modulators can be combined together using standard RF combiners or passive splitters used in reverse.

Thor Broadcast also provides RF splitters and combiners designed for CATV systems.

RF Splitters / Combiners:
https://thorbroadcast.com/product/1-x-2-to-1-x-128-fiber-optic-couplers.html

Typical CATV RF frequency range supported:

54 MHz – 1000+ MHz, which easily accommodates digital QAM channels.

Cost Advantage

Compared to the Technicolor COM3000 system , the Thor Broadcast solution should cost a small fraction of that amount while providing:

• High-definition digital channels

• Flexible expansion

• Integration of satellite, media players, and cameras

• Compatibility with existing coax infrastructure

1. SPTS vs MPTS on the 4-ADHD

You are correct that the unit supports:

• 4 × SPTS (Single Program Transport Streams)

• 1 × MPTS (Multi Program Transport Stream)

SPTS = one program per IP stream
MPTS = multiple programs combined into a single IP stream

2. Can SPTS be sent to different locations?

Yes.

Each SPTS carries only one program, but you can send each SPTS to a different destination (IP + port).

So effectively:

• Channel 1 → Site A

• Channel 2 → Site B

• Channel 3 → Site C

• Channel 4 → Site D

3. Same program to multiple locations

If you want to send the same program to 4 different remote sites using SPTS, then:

Yes — you would need to replicate that program across multiple inputs
(or use duplication upstream)

This results in 4 independent SPTS streams, each pointing to a different destination.

 Alternative (better approach):
If your network allows, you could also use:

• Multicast distribution, or

• A network-level duplication (router/server side)

This avoids duplicating inputs physically.

4. Using MPTS instead

Yes — selecting MPTS is a simpler way when sending all programs to one location.

• MPTS combines all 4 programs into one IP stream

• That stream is then received and demultiplexed on the receiving side

Important:

• Total bitrate will be ~15–20 Mbps (depending on encoding settings)

• Requires sufficient and stable bandwidth between locations

5. Modulator with single IP input

If your modulator accepts:

• One primary IP

• One backup IP

Then typically it expects one MPTS stream, not multiple SPTS streams.

In this case, yes —
the system works by combining multiple programs into a single transport stream (MPTS) and sending it to that IP.

6. IP addresses for control vs streaming

Good question.

• Control IP (management GUI) → used for configuration

• Data/streaming IP → used for video transport

7. MPTS to ASI functionality

Yes — our IP to ASI unit supports this.

You can:

• Input multiple SPTS streams, or

• Input one MPTS stream

And output:

A single ASI output carrying a combined MPTS

Limitation:

• Total bitrate must stay within ~19.3 Mbps (ATSC standard)

8. Number of programs in MPTS (SD vs HD)

Correct.

You can combine multiple programs, but total bitrate is the limiting factor.

Example:

• Good quality program ≈ 4–5 Mbps

• Total available ≈ 19.3 Mbps

So:

• ~4 programs → good quality

• 6–7 programs → lower quality

• Works better for low-motion content (news, talk shows)

Resolution (SD vs HD) matters less than bitrate per program.

9. Does your modulator behave the same way?

 Yes — if your modulator accepts IP input, it typically works the same:

• Receives MPTS

• Demultiplexes internally into channels

10. Using 4-ADHD as a distribution platform

You are absolutely correct.

The H-4ADHD can be used as a flexible distribution appliance, not just a point-to-point encoder.

However, when distributing over public or routed networks, please note:

 This requires proper network configuration

Basic concept:

• Encoder (TX side) must be on the same LAN as its router

• Destination IP = public/WAN IP of receiving site

• Required ports must be open and forwarded

On the receiving side:

• Router must port-forward incoming stream

• Forward to the IP of the decoder / IP-to-ASI unit

Example:

TX Side
Encoder IP: 192.168.2.136
Router: 192.168.2.1

RX Side
Public IP: 10.141.27.55
→ Port forwarded to local decoder (e.g., 192.168.1.50 port 1000

Final Note

Once you define:

• Number of sites

• Number of programs per site

• Network type (private vs public)

We can help you determine:

Exact number of units required
Best architecture (SPTS vs MPTS vs hybrid)