Petit HDMI RF MODULATOR

So if you have an old RF modulator, you're essentially making a channel; so on the other end, you need to decode that channel.

https://thorbroadcast.com/product/catv-rf-and-atsc-rf-to-hdmi-decoder-stb-8230.html

You can also take HDMI output from your Video source and make a Digital channel using H-HDMI-RF-PETIT modulator, HDMI IN - QAM RF Out, then decoded same way using QAM STB H-STB-QAM-ATSC

In order to circumvent the 500ms delay from the encoding times between the HDMI and Looopout you can bypass the HDMI completely and utilize both the RF ports on the Petit. Even though they say "RF IN" and "RF OUT", they can both be used to send RF signals Out without a delay because they are both being encoded at the same rate. You can even connect an RF Splitter/Combiner to those ports so you can connect TVs all throughout your facility at the same encoding time. 

Do you have any more information about what the application necessitates besides HDMI? Do you require certain resolution or audio capability? Is the latency or size of a unit an issue? We have a plethora of units that can fit the information you provided. The Petit would seem fine, or the AC3-CMOD, we also have multi-channel units like the Thunder-4... All can take HDMI and output to RF

this is a link to the 8 channel H-HDXOAX-8

https://thorbroadcast.com/product/1-8-hdmi-digital-rf-modulator-cc-closed-captioning.html/95

2) The modulator should be able to feed all of the TV's. I would think you'd want to put it near the other Comcast gear. But it does it's 2 blocks away? Is there another headend room or electronics closet closer to the facility you can put the equipment in? In either case, you can use the RF Petit, or you can use something like the Thunder-4 for multiple HDMI inputs. All you need is a coax combiner, to get the feed from Comcast and our units together. You also should find out which channels are being unused by Comcast so you can put the QAM channels on open frequencies. Comcast also to Inject local video insertion at channel 134 it will show as a channel 1901,1902,1903,1904

Please check those HMI /SDI PTZ cameras, very easy to use with our modulator, just connect the HDMI output to the modular input, and your video will be converted to modulated RF
 

https://thorbroadcast.com/product/maximuscontrol-professional-grade-video-ptz-controller.html

Unfortunately it would not work, because your output from the Sony is an analog modulated ch 3 or 4 , the STB would only work with a digital QAM or ATSC signal.

But you could do the following.

Use the HDMI out to our HDMI RF digital modulator - Coax out to the STB
The modulator would produce Digital QAM which the STB would see, You will have much better video quality as well since the video will be in HD.

We can offer you the following prices :
Modulator $450
QAM STB  125
this is the link and application example :

This is a Digital modulate and generate digital QAM or ATSC, it can
not generate analog channel.
You can use this QAM STB after the modulator, it will decode Video to
HDMI, but also it has analog NTSC RF output ch 3 or ch 4 - it is
selectable.
This way you can get Analog RF from the QAM source

This is the link:
https://thorbroadcast.com/product/qam-catv-rf-and-atsc-rf-to-hdmi-decoder-stb-8230.html

If you have the Thor logo only, it means the modulator does not recognize the incoming HDMI video. Please check the second LED "LINK LOCK"; it is probably OFF. It indicates the Incoming Video Link indicator. OFF means that it is not recognizing the incoming video resolution.

Please do the following:

Log in to your HDMI source like DVD player or Set top box and select only one static video resolution
- 720p, 1080i, or 1080p, but just ONE of them, and uncheck the "Auto" resolution.

Reboot the device, connect to the modulator.
Now you should see the second LED "LINK LOCK" turn ON (turn Green).
Now you should see your content modulated on the TV.