How good is this ATSC modulator?

[Videogamer555]

I've never before seen an 8VSB ATSC modulator that cost under $1000, until today. I found this here http://www.mcmelectronics.com/product/STELLAR-LABS-33-11980-/33-11980 which costs only $299. It appears to allow independent setting of the digital channel number and the physical channel (transmit frequency). It looks like a good deal, but I'm not sure. Before I spend that much money, I'm going to want to get some input from others who used it.
Here are some things that I'd like to know, and hopefully the community here will be able to provide some definitive answers.
Does it work with sound, or only video? (One review on Amazon, where it's also being sold, said they don't get sound out of their TV when using it)
Does it allow setting of the sub-channel number? (I can't find any documentation on this, so is it limited to using only the first sub-channel for each channel?)
Does it work with 1080p video? (one review on Amazon said it was downscaling their video from 1080p to 720p)

I don't know if the complaints on the Amazon reviews were just from people with defective units, or if these are actual problems with the device, so I hope some users here on this forum will have used this device, and will be able to provide some definitive answers.

[usually_quiet]

The audio listed in the specs at your link is "MPEG-I Layer 2". OTA TV and digital cable TV in the US uses Dolby Digital/AC3. Many if not most N. American TVs won't be able to decode the audio.

[Videogamer555]

The audio listed in the specs at your link is "MPEG-I Layer 2". OTA TV and digital cable TV in the US uses Dolby Digital/AC3. Many if not most N. American TVs won't be able to decode the audio.

Why can most digital TV's only use Dolby? I thought all ATSC compatible TV's were required to be able to use Dolby (not reject a signal that uses Dolby) for audio. I didn't know that the ATSC standard required that TVs use ONLY Dolby (reject any signal not using) Dolby.

[usually_quiet]

The audio listed in the specs at your link is "MPEG-I Layer 2". OTA TV and digital cable TV in the US uses Dolby Digital/AC3. Many if not most N. American TVs won't be able to decode the audio.

Why can most digital TV's only use Dolby? I thought all ATSC compatible TV's were required to be able to use Dolby (not reject a signal that uses Dolby) for audio. I didn't know that the ATSC standard required that TVs use ONLY Dolby (reject any signal not using) Dolby.

Broadcasters are legally required to follow the specification, and Dolby Digital/AC-3 audio is an official requirement of the ATSC 1.0 standard. MPEG 1 Layer 2 is not. (MPEG 1 Layer 2 was considered while the ATSC 1.0 standard was under development, but was ultimately rejected.)

If only Dolby Digital/AC-3 is allowed in ATSC broadcasts, why would you expect a TV to be able to decode other digital audio formats delivered via the tuner?

For what it is worth, I have recorded the broadcast streams for hundreds of OTA TV broadcasts since 2010 (using PC TV tuners), and have seen only Dolby Digital/AC-3.

[sambat]

It says that the RF output is 'ATSC Standard' - I took the MPEG 1 Layer 2 audio as referring to the usb input.

[usually_quiet]

It says that the RF output is 'ATSC Standard' - I took the MPEG 1 Layer 2 audio as referring to the usb input.

I think it is more likely that the section of the specs that says "Encoding mode MPEG2 Audio format MPEG-I Layer 2", refers to the device output.

The specs say:"USB input Plays AVI and MOV from flash memory". When was the last time that you saw MPEG2 video and MPEG-1 Layer 2 audio in either of those containers?

There is a thread at avsforum about this device: http://www.avsforum.com/forum/25-hdtv-technical/2700377-stellar-labs-atsc-hd-modulator.html

[Edit]This post indicates the audio is MPEG-1 Layer II: http://www.avsforum.com/forum/25-hdtv-technical/2700377-stellar-labs-atsc-hd-modulator...l#post51020937

[Videogamer555]

This one sounds better, just by its description.
http://www.provideoinstruments.com/1-CHANNEL-HDMI-Video-To-Coax-1080P-Dolby-HD-Modulat...OD-2_p_17.html

It uses Dolby sound, and allows setting of both channel and sub-channel numbers. It also works up to 1080p for image size. It even allows you to select the rf signal type (ATSC, QAM, DVBT, DVBC, ISDBT, and DMBT).

The price is $495, which is still quite cheap for being a digital tv modulator. Has anybody on these forums tried one yet? If you have, please let me know if it's a good quality product.

[usually_quiet]

avsforums has a user thread for the Vecoax modulators as well: http://www.avsforum.com/forum/25-hdtv-technical/1656321-pvi-vecoax-micromod-experiences.html

[mattchewjohn]

This one sounds better, just by its description.
http://www.provideoinstruments.com/1-CHANNEL-HDMI-Video-To-Coax-1080P-Dolby-HD-Modulat...OD-2_p_17.html

It uses Dolby sound, and allows setting of both channel and sub-channel numbers. It also works up to 1080p for image size. It even allows you to select the rf signal type (ATSC, QAM, DVBT, DVBC, ISDBT, and DMBT).

The price is $495, which is still quite cheap for being a digital tv modulator. Has anybody on these forums tried one yet? If you have, please let me know if it's a good quality product.

PVI's equipment seems sketchy... https://www.scribd.com/document/402862960/Pro-Video-Instruments-encoder-HDMI-modulator...ade-in-America

[ATSC]

I found recently and purchased HDMI HD 1080p ATSC modulator for $386 from thorbroadcast H-HDMI-RF-PETIT, works grate, video and audio quality is like original HDMI Roku source, easy to use, I sending my own CH30 ATSC RF to all 8 TV's. They have also multiple HDMI input modulators but 1 was enough for my personal use.I might get one more for my security camera so I can see it on my TV as another channel.
This is the link to specifications https://thorbroadcast.com/product/petit-hdmi-rf-modulator-1.html