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Discussion Starter #1
Are there any reasonable options out there that can receive over the air ATSC signals and convert them to QAM, outputting them at a selected frequency and program #?

Google searches turn up many- but it is difficult to track them down, or if you do they are outrageously priced. I did find one affordable offering from LG... an OAR unit designed for the hospitality business that was about $1k. But apparently it has been discontinued.

Where I live our local cable system carries two stations in SD only from a neighboring market. I'd like to pick up one of these transcoders to "replace" the SD versions with the HD versions from my OTA antenna. Yes, I realize I will lose the other SD channels on the same frequencies as the channels in question. I don't watch those anyway however, and they aren't even in my channel list currently. There are two other "local origination" channels available that I could use to add the other two OTA channels I don't get on cable. I wouldn't have guide data, but I could get everything on one box as opposed to having one TiVo dedicated to cable, and another dedicated to antenna. I could add cablecards to both.
 

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Antenna > tuner > agile QAM modulator > combiner


 

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AntAltMike can help you with the details; he knows more about it than I do. You will probably need a cable notch filter for the modulator output channel placement.
 

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I looked up the 7003 and it seems to output only an analog signal. cpalmer2k is looking for an HD signal modulated onto a QAM carrier.
Am I missing something?
John
 

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Maybe not, maybe I missed it.

It does have HDMI and component output for what I thought would be HD



The puzzle to solve would be the interface between the tuner and the modulator, which is why I thought of Mike. The modulators that I looked at have an Asynchronous Serial Interface, or ASI Input.
 

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Discussion Starter #6
I did consider the modulator route. I guess I could hook up a splitter and feed lines to several of the Homeworx HD Tuner boxes with HDMI outputs (cheaper than the 7003's) and feed them into a modulator like the PVI models.

I was hoping more for an "all in one" solution like the discontinued LG OAT100R though :-(
 

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Should be SIMPLE, but there is NO WAY it's gonna be "CHEAP": Just hook the HDMI Output of ANY HD STB [use R/C to select Channel] to the HDMI Input of ANY Clear QAM Modulator [select ANY TX Frequency and whether QAM64 or QAM256], such as fol. which came up as the least expensive on Amazon [$895 each]:
http://www.pviusa.com/MICROMOD-Compact-HD-RF-Modulator_p_30.html [User Control via USB I/F to PC]
https://www.amazon.com/PVI-MICROMOD-Channel-Digital-Modulator/dp/B00F7NDQEC
https://www.amazon.com/gp/product/B00F7SE5MO [Alternative ATSC Modulator compatible with ANY DTV]
And Dual Channel Thor Broadcasting H-2ADHD [about $2000 or $1000/channel, much less if USED]:
https://www.amazon.com/gp/product/B...3_5?ie=UTF8&psc=1&refRID=MG8CKXG24SY63R9W5AQ1
For just a bit more, ZeeVee ZvPro 810 [$1146]:
https://www.amazon.com/ZeeVee-ZvPro810-Video-Distribution-Modulator/dp/B00IMN1VCI
https://www.zeevee.com/zvpro-800-series-hd-video-distribution.html

If you want more than one [or 2 with Dual Ch Thor] QAM Channels, use standard Multi-Port RF Combiner to sum the various QAM Channels....or check out Multi-Channel Clear QAM [and ATSC] Modulators from Thor Broadcasting that are in same ballpark cost wise as above solutions on a per channel basis:
http://thorbroadcast.com/sklep-205

BTW: There are also DIY Clear QAM [and ATSC] Modulator Solutions using Downloadable Software to a Software Defined Radio (SDR) Modulator Card for a PC.

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Be careful you do NOT use a QAM Modulator that conforms to EURO DVB-C Specs, with non-compatible 8 MHz (or 7 MHz) Channel Spacing.

Following [US Mfr] Cablevision DVQAM-1 [$895], and dual channel DVQAM-2 [$1379 or $690/channel] HDMI-to-QAM Modulators [erroneously] CLAIM conformance to EURO DVB-C, but Specs say it ONLY supports 6 MHz Channel Spacings, so it's PROBABLY intended for use with those North American STB/DTV's that support Clear QAM. BTW: I THINK that "Dual Mode H.264 / MPEG4 AVC" in the Spec PROBABLY means it supports H.264 (MPEG4 AVC) in ADDITION to the standard MPEG2 used on U.S. Clear QAM Channels. I would suggest further research:
http://www.northamericancable.com/specsheets/DVQAM.pdf
http://www.markertek.com/product/dv...channel-digital-qam-modulator-with-hdmi-input
http://www.markertek.com/product/dvqam-2/dvqam-2-two-channel-digital-qam-modulator-with-hdmi-input
More on this subject found in a similar thread:
http://www.avsforum.com/forum/25-hdtv-technical/2593609-my-first-experience-iptv.html#post47181273

BTW: Blonder Tongue makes a so-called "ATSC-to-QAM Transcoder"....but in reality it is a Tuner that accepts either ATSC or Clear QAM Input Signals and OUTPUTS a Digital Signal in [professional studio] ASI format.
 

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I did consider the modulator route. I guess I could hook up a splitter and feed lines to several of the Homeworx HD Tuner boxes with HDMI outputs (cheaper than the 7003's) and feed them into a modulator like the PVI models.

I was hoping more for an "all in one" solution like the discontinued LG OAT100R though :-(
I had offered that product to some of my hotel customers, but before any of them expressed interest, it was no longer available and I never got to even test one on my bench.

The functionality of it is presently incorporated into "cards" that plug into DISH Network and DirecTV headends, but not only would you need a chassis and power supply, I'm told that it isn't authorized to transcode unless the card is registered to a subscribed, DirecTV or DISHNetwork customer account.

I haven't kept up with Tivo DVR equipment over the last decade. Do they presently NOT have 8VSB broadcast tuners in them?
 

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Discussion Starter #10
I had offered that product to some of my hotel customers, but before any of them expressed interest, it was no longer available and I never got to even test one on my bench.

The functionality of it is incorporated into "cards" that plug into DISH Network and DirecTV headends, but not only would you need a chassis and power supply, I'm told that it isn't authorized to transcode unless the card is registered to a subscribed, DirecTV or DISHNetwork customer account.

I haven't kept up with Tivo DVR equipment over the last decade. Do they presently NOT have 8VSB broadcast tuners in them?
They do, but the Roamio models are Cable OR Antenna. They no longer support both simultaneously. In this case the two channels are carried on cable (in SD only), and have guide data available. If I merged them with my existing feed then I could easily watch and record from them just like all my other channels. These are the only SD channels I keep in my channel list, so wiping out their frequencies wouldn't be a loss to me. The PVI MicroMod modulators might be a good option. They're somewhat reasonable (given the cost of modulators) and I likely could use a usb-->barrel adapter to power them from the USB port on the tuner box.
 

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BTW: Blonder Tongue makes a so-called "ATSC-to-QAM Transcoder"....but in reality it is a Tuner that accepts either ATSC or Clear QAM Input Signals and OUTPUTS a Digital Signal in ASI format.
Blonder Tongue does make the AQT mini-mods that will do 8VSB -> QAM:
https://www.tonercable.com/pdf/AQT_UserMan_651219100C.pdf

I'm not sure if they've been replaced by the 8-channel models though. And you then get into the mini-mod chassis, PSU, etc which may price it out of range....
 

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The only B-T "Transcoder" product I initially saw when searching was the following, which receives ATSC or Clear-QAM and outputs ASI:
http://www.blondertongue.com/products/micro-digital-demod-to-asi

Yes, the similar looking B-T AQT plug-in Mini-Module is in fact an ATSC-TO-QAM TRANSCODER as desired...if you could actually FIND any:
http://www.markertek.com/product/aqt/blonder-tongue-aqt-atsc-qam-transcoder
http://www.blondertongue.com/UserFiles/file/Solutions/documents/AQT_Presentation.pdf
However note that each [abt $800?] AQT Transcoder must plug into a common [abt $1000] Rack Mount Chassis with Power Supply, so it's a LOT more expensive. Discontinued from Markertek, Solid Signal and no longer listed on B-T Website...and I couldn't find any available in a quick search...although there may be USED ones on FleaBay:
http://www.blondertongue.com/shop-by-department/digital-catv/transcoders

Fol. B-T Rack-Mount 8-Channel ATSC-TO-QAM TRANSCODER [$5,561] seems to be the least expensive still available:
http://www.blondertongue.com/atsc-qam-transcoder-6280.aspx [FREE Registration required to see prices]
 

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http://www.blondertongue.com/shop-by-department/digital-catv/transcoders

Fol. B-T Rack-Mount 8-Channel ATSC-TO-QAM TRANSCODER [$5,561] seems to be the least expensive still available:
http://www.blondertongue.com/atsc-qam-transcoder-6280.aspx [FREE Registration required to see prices]
As the Diamond Mine's radio commercial says: "Nobody pays retail anymore. Why should you?" Multicom has it for $3,995, but they might not sell to you, and Marketek has it for $4,299, and they sound like someone who will sell to anyone.

I can't find my Blonder Tongue registered screen name on this computer, but rather than trying all the possibilities, I found that product fully documented in the Toner Cable online catalog here: https://www.tonercable.com/products...nscoder-8x8-vsb-qam-to-qam-ip.php?version=121.

I still don't see what cpalmer2k is attempting for a configuration. Does his DVR have a cable card? If not then I don't see how it could presently process encrypted signal from the cable company. If it has a cable card and HDMI out, I still don't see how he appends modulated, broadcast-sourced QAM channels into this.
 

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Discussion Starter #14
I still don't see what cpalmer2k is attempting for a configuration. Does his DVR have a cable card? If not then I don't see how it could presently process encrypted signal from the cable company. If it has a cable card and HDMI out, I still don't see how he appends modulated, broadcast-sourced QAM channels into this.
Yes, my TiVo has a functioning CableCard in it that works perfect for cable channels. Basically I'm trying to take the over the air versions of two local channels, and "replace" the cable company's standard definition versions of those channels by combining the QAM output of those two channels from my modulators with the cable line going into my TiVo.

In this case one local channel is being broadcast on the equivalent of 8.8 by the cable company, and the other is on 8.9. So I wipe out channel 8 on the cable line with a notch filter, then combine the 8.8/8.9 coming from my modulators with the cable line using a combiner.

Am I incorrect in assuming that the TiVo would then see MY 8.8 and 8.9 as opposed to the cable company's and translate it to the proper actual channel using the cable card channel map?
 

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Am I incorrect in assuming that the TiVo would then see MY 8.8 and 8.9 as opposed to the cable company's and translate it to the proper actual channel using the cable card channel map?
Yes, not quite correct...you couldn't modulate them both to the same physical channel # (which is what your TV is using to # them) or the freqs would conflict weith each other.

You'd need to multiplex the two stream together first and THEN modulate that stream, if you really wanted them to show up on the same physical channel. Or else you'd need to modulate them to two different channel #s. Either way you can't make them 8.x because that's what you DON'T want to notch out with the filter. (to get 8.1-8.6, etc) You could modulate them to some other physical channel # and use 8.8/8.9 virtual channel # possibly, if you can set that in your mux/device.
Sorry, this ain't easy
 

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If you are on a 135 channel cable system, but if your TIVO tunes higher than that AND if your modulators output higher than that, then MAYBE you could QAM modulate to above them, or you could get a fairly high frequency rolloff low-pass filter, like a commonly available channel 117 and take your chances with what gets scraped off.

I think the insurmountable hurdle will be that the cable card may commandeer the Tivo tuner and it might only tune in accordance with the cable TV company's channel plan. About a decade ago, one of my hotel customers bought a dozen Philips big screen TV that were cable card capable, and I scanned them for the unscrambled analog, NTSC lineup of about 60 channels and I found and tuned them all, but each time I took the TV out of scan mode, it could only tune channels 2-36, and of course, hotel TVs have locked-down tuners, so a person with a guest remote cold not access the higher numbered channels.

After a day of piddling unsuccessfully with those TVs, I had to tell the customer that it was up to them to get to the bottom of this.

It turned out that not only were these TVs cable card capable, the seller had given them and installed cable cards at no cost to them and without telling them they were delivered that way, and the cable card's programming countermand or overrode what I developed for a channel lineup during set up. All it took to get those TVs to recognize my channel lineup was to remove the cards. The TVs didn't even need to be rescanned.
 

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Discussion Starter #18 (Edited)
I might have confused you with some of what I wrote above. Let me see if I can clarify it:

channel #1 that I want to replace is actually transmitted as program #8 on 18300khz (i.e qam 8.8) according to my TiVo analysis page, which corresponds to cable channel 2 on our system.

channel #2 is transmitted on 8.9, and is cable channel 15.

The way I understand it (correct me if I'm wrong) the channel map on the cable card tells the TiVo that when I tune to channel 2 it should show me program 8 coming in on 18300khz (i.e coming in on 8.8), or if I tune to channel 15 it should show me program 9 from the same frequency.

So if I erase the 18300khz block on the cable line, and insert my new modulated signals on 8.8 and 8.9 shouldn't the TiVo read them the same way as if it were the original cable company signal? EDIT: After re-reading I understand what you're saying about muxing the streams. In this case I would have to buy the two input PVI modulator so it would combine the two signals, and output 8.8 and 8.9 from the same modulator.

Assuming that was done, wouldn't the TiVo interpret it the same? Again these channels are already in the channel map, and exist. I'm just replacing their SD version with my modulated HD version. Sacrificing the other SD only channels on that frequency in the process.
 

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From his description, it appears that he plans to use Single Channel Insertion Filter type devices to attenuate two existing Channel Positions and REPLACE them with two Inserted QAM Channels from QAM Modulators, "Transcoded" from two OTA ATSC Channels Input from existing OTA Tuners via HDMI I/F's.

Since OTA Source is NOT Encrypted, that would NOT be an issue. It would be his responsibility to read User Manuals and talk to User Support on exactly HOW to set up the "QAM Modulator"....shouldn't be that big a problem, although initially a particular unit may require a PC to setup Channel Frequency, PSIP and other Operator selections.

Of course, the Channel Insertion Filters would also kill each Upper & Lower Adjacent Channel [and perhaps Next Adjacent Channels???] which may or may not be a problem....or perhaps use some different Channel Frequencies that his users don't care about....

OP should provide clarification if this is not correct....
 

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