VideoHelp Forum

+ Reply to Thread
Results 1 to 14 of 14
Thread
  1. Member
    Join Date
    Oct 2021
    Location
    Wheeling WV USA
    Search Comp PM
    we had cheap mini NTSC and PAL analog modulators many years ago. but digital modulators still seem to be high-end and large if i am no good at looking for ATSC stuff. for low-end, i would expect some tradeoffs, of course. a friend has a business where a number of TVs around the building get OTA TV via coax fed from a single antenna. he wants to have some HD security cameras to be fed on spare RF channels. he's already converting them to NTSC and doing analog on channels 5 and 6 but would like to go digital. the only suggestion i have offered is digitizing on a PC and running it over his fiber network and watching over various PCs. but is still a committed PC for the scan. i didn't find out what his cameras output but the way he talked they could be HDMI or HD-SDI. i suspect if a modulator is a mismatch conversion between is not so much.
    Quote Quote  
  2. There is few options, some of them easy to use but more expensive, some of them require some personal effort but can be reasonably cheap.
    Cheap options assume SDR (Software Defined Radio) and usually GNU Radio as a framework - something like: https://jeremyclark.ca/wp/telecom/gnu-radio-atsc_8vsb-transmitter-simulation/ ; https://wiki.gnuradio.org/index.php/ATSC with perhaps some small uComputer like RPi as a core and for example cheap SDR board like https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-bo...ml#eb-overview.
    more expensive but almost ready to use is dedicated ATSC modulator like https://www.dektec.com/products/USB/DTU-215/ (in fact this is also SDR solution that use PC CPU to generate signal).
    Alternatively ebay and some used IP based modulator with ATSC support (as new modulation for ATSC 3.0 is used then it may be sane approach).
    There is a chance that some China companies produce some customer tailored solutions...
    Quote Quote  
  3. Member
    Join Date
    Aug 2006
    Location
    United States
    Search Comp PM
    Originally Posted by Skaperen View Post
    we had cheap mini NTSC and PAL analog modulators many years ago. but digital modulators still seem to be high-end and large if i am no good at looking for ATSC stuff. for low-end, i would expect some tradeoffs, of course. a friend has a business where a number of TVs around the building get OTA TV via coax fed from a single antenna. he wants to have some HD security cameras to be fed on spare RF channels. he's already converting them to NTSC and doing analog on channels 5 and 6 but would like to go digital. the only suggestion i have offered is digitizing on a PC and running it over his fiber network and watching over various PCs. but is still a committed PC for the scan. i didn't find out what his cameras output but the way he talked they could be HDMI or HD-SDI. i suspect if a modulator is a mismatch conversion between is not so much.
    The video and audio from HDMI has to be encoded to meet the ATSC/QAM standard and formatted for transmission so an ATSC modulator can't be as inexpensive as an NTSC RF modulator.

    I found an ATSC modulator on Amazon that creates an ATSC or QAM signal on a channel selected by the user from an HD HDMI source. Since each camera needs its own $255 modulator, this is not a cheap solution, The units can be daisy-chained using their RF-in and RF-out to combine their signals plus the signal from an antenna. https://www.amazon.com/Modulator-Route-1080P-Ethernet-Setting/dp/B08B1VWPLP/
    Last edited by usually_quiet; 2nd Nov 2021 at 21:09.
    Ignore list: hello_hello, tried, TechLord, Snoopy329
    Quote Quote  
  4. Member Cornucopia's Avatar
    Join Date
    Oct 2001
    Location
    Deep in the Heart of Texas
    Search PM
    Ultimately, you might find that standard network streaming is a more straightforward and economical solution.


    Scott
    Quote Quote  
  5. Member
    Join Date
    Aug 2006
    Location
    United States
    Search Comp PM
    Note that while the Souka ATSC modulators in my other post have an ethernet connection, as far as I can tell, it is only used to control/configure the devices with a computer. I didn't see any indication that the ethernet connection can also stream video over a network.
    Ignore list: hello_hello, tried, TechLord, Snoopy329
    Quote Quote  
  6. Raspberry Pi or similar uC can be used as HDMI source and IP decoder so in overall this can be the best possible combination. Probably RPi is sufficiently powerful also to produce ATSC signal with help of the GNU Radio where ATSC modulator is freely available.
    Quote Quote  
  7. Member
    Join Date
    Oct 2021
    Location
    Wheeling WV USA
    Search Comp PM
    Originally Posted by Cornucopia View Post
    Ultimately, you might find that standard network streaming is a more straightforward and economical solution.


    Scott
    ultimately, i agree. i think i might need to bang that into his head frequently enough. maybe i should put the OTA signals on his network and suggest he pull all that coax and sell it. then any PC can watch TV or perps trying to break in. i just need to demod a bunch of channels on one PC. i think he gets about 10 of them, though.
    Quote Quote  
  8. Video Restorer lordsmurf's Avatar
    Join Date
    Jun 2003
    Location
    dFAQ.us/lordsmurf
    Search Comp PM
    Originally Posted by Cornucopia View Post
    Ultimately, you might find that standard network streaming is a more straightforward and economical solution.
    Scott
    That's it.
    In the video hobby community, it went from VHS > DVD > streaming.
    No HD discs, no digital/ATSC recording, non-TiVo PVRs largely failed.
    And the consumer hobby community did somewhat decide what is (and isn't) available now.
    Quote Quote  
  9. Member
    Join Date
    Aug 2006
    Location
    United States
    Search Comp PM
    Originally Posted by Skaperen View Post
    Originally Posted by Cornucopia View Post
    Ultimately, you might find that standard network streaming is a more straightforward and economical solution.


    Scott
    ultimately, i agree. i think i might need to bang that into his head frequently enough. maybe i should put the OTA signals on his network and suggest he pull all that coax and sell it. then any PC can watch TV or perps trying to break in. i just need to demod a bunch of channels on one PC. i think he gets about 10 of them, though.
    There are a couple of networkable TV tuners that might make your job easier Silicondust's HDHomeRun Flex Quatro - HDFX-4US (with 4 x ATSC Tuners) or SiliconDust's HDHomeRun Flex 4K - HDHR5-4K (with 2 x ATSC Tuners and 2 x ATSC/ATSC 3.0 Tuners).

    I have Silcondust's now-discontinued HDHomeRun Prime CableCARD tuner and have been a satisfied customer for a few years.

    [Edit] If your friend's business has more than 4 TVs then Silcondust also has commercial tuners available: https://www.silicondust.com/hdhomerun/commercial/

    I should mention that ATSC 3.0 is still more or less experimental and few if any TV stations are currently broadcasting in 4K. All or nearly all ATSC 3.0 channels are broadcast in HD resolution. Silicondust's software for ATSC 3.0 TV is still a work in progress.
    Last edited by usually_quiet; 4th Nov 2021 at 17:27.
    Ignore list: hello_hello, tried, TechLord, Snoopy329
    Quote Quote  
  10. If you insist to use existing coax solution then perhaps MoCA technology can be alternative.
    Quote Quote  
  11. Member
    Join Date
    Oct 2021
    Location
    Wheeling WV USA
    Search Comp PM
    Originally Posted by usually_quiet View Post
    [Edit] If your friend's business has more than 4 TVs then Silcondust also has commercial tuners available:
    something like 40. they all are ATSC capable and can tune the OTA RF. i don't know how convenient it is to connect them to a PC or RPi. i think some of them already are so connected for other uses like the conference room ones. last time we talked about this i didn't bring up alternatives though i was thinking of some possibilities.

    i think the channels he gets are: 2, 4, 7, 9, 11, 13, 21, 27, 33. i know the Pittsburgh RFs but not Youngstown.
    Quote Quote  
  12. Member
    Join Date
    Oct 2021
    Location
    Wheeling WV USA
    Search Comp PM
    Originally Posted by pandy View Post
    If you insist to use existing coax solution then perhaps MoCA technology can be alternative.
    he wants to put a few TV streams he gets on his PC into his ATSC system. the basic solution to that is getting the streams and modulating them to available RF channels (plenty as he is using only 9 or 10). the alternative is to do everything over his IP network which seemed rather speedy when i set up a couple servers for him a few years ago. so the question i'll pose to him is if he can network the TVs. i just envision him doing it all, streams and OTA, on his network. it would be a cleaner solution and he could pull all that coax and sell it. that and get rid of the electrical grounding problems he's had with it.
    Quote Quote  
  13. Member
    Join Date
    Aug 2006
    Location
    United States
    Search Comp PM
    Originally Posted by Skaperen View Post
    Originally Posted by usually_quiet View Post
    [Edit] If your friend's business has more than 4 TVs then Silcondust also has commercial tuners available:
    something like 40. they all are ATSC capable and can tune the OTA RF. i don't know how convenient it is to connect them to a PC or RPi. i think some of them already are so connected for other uses like the conference room ones. last time we talked about this i didn't bring up alternatives though i was thinking of some possibilities.
    Under those circumstances, tuning the signals provided by the antenna over coax with each TVs tuner makes more economic sense than using any of the Silicondust products.

    Pittsburgh has 3 ATSC 3.0 channels but they don't provide any networks that are unavailable via Pittsburgh's regular ATSC broadcast stations and their signals may not reach as far as Youngstown, so there is no need for ATSC 3.0 tuners either.

    [Edit] If it was economically feasible to connect 4 antennas to a TECH5-16US-4X4 and connect an RPi to each TV then if I understand the product description correctly, TECH5-16US-4X4, would work for supplying up to 16 channels at a time for site-wide multicast streaming.

    Originally Posted by Skaperen View Post
    i think the channels he gets are: 2, 4, 7, 9, 11, 13, 21, 27, 33. i know the Pittsburgh RFs but not Youngstown.
    rabbitears.info may be able to help with the Youngstown RFs https://www.rabbitears.info/market.php
    Last edited by usually_quiet; 4th Nov 2021 at 23:03.
    Ignore list: hello_hello, tried, TechLord, Snoopy329
    Quote Quote  
  14. Member
    Join Date
    Oct 2021
    Location
    Wheeling WV USA
    Search Comp PM
    he is located near Weirton. before digital i could get 2 of the 3 Youngstown stations despite being on the side of a hill facing away from Youngstown, here near Wheeling. i don't get any Youngstown digital, but he does as he has a clear view in just about all directions. i can get channel 36 (PBS) from western Maryland when i face my portable antenna that way. it breaks up a bit, but i suspect a larger UHF antenna would improve that.
    Quote Quote