Reasonable ATSC-->QAM Transcoding Option? - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 31 Old 10-03-2016, 08:51 AM - Thread Starter
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Reasonable ATSC-->QAM Transcoding Option?

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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post #2 of 31 Old 10-03-2016, 09:37 AM
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Antenna > tuner > agile QAM modulator > combiner



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post #3 of 31 Old 10-03-2016, 10:47 AM
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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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post #4 of 31 Old 10-03-2016, 11:01 AM
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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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post #5 of 31 Old 10-03-2016, 11:19 AM
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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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post #6 of 31 Old 10-03-2016, 11:43 AM - Thread Starter
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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 :-(
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post #7 of 31 Old 10-03-2016, 11:59 AM
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post #8 of 31 Old 10-03-2016, 12:57 PM
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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-Compa...ator_p_30.html [User Control via USB I/F to PC]
https://www.amazon.com/PVI-MICROMOD-.../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/B0...G24SY63R9W5AQ1
For just a bit more, ZeeVee ZvPro 810 [$1146]:
https://www.amazon.com/ZeeVee-ZvPro8.../dp/B00IMN1VCI
https://www.zeevee.com/zvpro-800-ser...tribution.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.

================================================== =========
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/dvq...ith-hdmi-input
http://www.markertek.com/product/dvq...ith-hdmi-input
More on this subject found in a similar thread:
https://www.avsforum.com/forum/25-hdt...l#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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post #9 of 31 Old 10-03-2016, 12:57 PM
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Quote:
Originally Posted by cpalmer2k View Post
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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post #10 of 31 Old 10-03-2016, 01:18 PM - Thread Starter
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Quote:
Originally Posted by AntAltMike View Post
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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post #11 of 31 Old 10-03-2016, 01:41 PM
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Quote:
Originally Posted by holl_ands View Post

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_U...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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post #12 of 31 Old 10-03-2016, 02:24 PM
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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/product...l-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...qam-transcoder
http://www.blondertongue.com/UserFil...esentation.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...tv/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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post #13 of 31 Old 10-03-2016, 03:02 PM
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Quote:
Originally Posted by holl_ands View Post
http://www.blondertongue.com/shop-by...tv/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/...hp?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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post #14 of 31 Old 10-03-2016, 03:26 PM - Thread Starter
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Quote:
Originally Posted by AntAltMike View Post
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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post #15 of 31 Old 10-03-2016, 03:48 PM
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How will you add the PSIP?
https://www.google.com/?gws_rd=ssl#q=psip

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post #16 of 31 Old 10-03-2016, 03:52 PM
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Quote:
Originally Posted by cpalmer2k View Post

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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post #17 of 31 Old 10-03-2016, 04:18 PM
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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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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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post #19 of 31 Old 10-04-2016, 12:42 AM
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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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post #20 of 31 Old 10-04-2016, 01:22 PM
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PVI MicroMod primarily uses Front Panel. And USB I/F for F/W Updates & TS File Management:
http://www.pviusa.com/MICROMOD-Compa...ator_p_30.html
https://www.cyberselect.co.uk/sites/...Nov%202013.pdf
https://www.avsforum.com/forum/25-hdt...periences.html

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post #21 of 31 Old 10-04-2016, 03:49 PM
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This plan has about zero chance of success.

First of all, as I pointed out above, we have no idea to what extent the cable card's authorization countermans the tuner. I can't send any old Nagravision signal into a DISH Network receiver and tune it even though it is electronically compatible, because the tuner's software will ignore it.

Second, when deleting channels at UHF frequencies, a suitable, single channel elimination filter costs a thousand dollars and will degrade the upper and over adjacent channels, and you won't know in advance what they are, and the cable company can remap tomorrow and they will be different channels tomorrow. If you want to experiment as cheaply as you can, then get one modulator on a returnable basis, and use a cheap lowpass filter, like a $3 UVSJ. which will pass up to about cable channel 30 and see if you can tune your modulated channel and if you can't, then send the modulator back. If you can, then buy a Channel Vision channel 117 (or thereabouts) lowpass filter and try to determine what you channels and services you lose by lopping off the top of the cable TV spectrum.

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post #22 of 31 Old 10-05-2016, 07:39 AM - Thread Starter
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Searching the TiVo forums yesterday I found many instances where people have modulated various things (Apple TV, DirecTV receivers, etc) into their TiVo systems. So it can work- so long as the channel you put it on is in the channel map for the card it will tune it.

The problem in this case is going to be the adjacent channel issue. The frequency below this one carries C-SPAN HD, which I do use.
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post #23 of 31 Old 10-05-2016, 02:50 PM
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Quote:
Originally Posted by cpalmer2k View Post
Searching the TiVo forums yesterday I found many instances where people have modulated various things (Apple TV, DirecTV receivers, etc) into their TiVo systems. So it can work- so long as the channel you put it on is in the channel map for the card it will tune it.
Can you furnish a link to those threads?



Quote:
The problem in this case is going to be the adjacent channel issue. The frequency below this one carries C-SPAN HD, which I do use.
That and the fact that high frequency, single channel elimination filters I've used successfully in that frequency range cost around $1,000 each, last time I priced them. I see that the Pico model which can be had for $500 or so, can eliminate up to channel 62. There are filters for under 40 with good depth and shielding that take out typically, 64-70, 71-75, and maybe 76-82

What is your source for the present cable channel mapping information?

Isn't the output of your modulator channel? If so, what is it's range? Have you looked to see what is above 117, which can be eliminated cheaply?
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post #24 of 31 Old 10-05-2016, 05:07 PM
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He's trying to place it specifically on physical 8.8/8.9 so he can use the guide and DVR from the Tivo/CableCARD.

Ah, I missed you had a CableCARD the first go. It would work if you could place it there exactly, but the problems so far:

- The filtering, as was pointed out about losing the adjacent channels. Have to determine if you're ok with losing them
- The fact you want it on physical 8 - 8.8/8.9 implies that there are 8.1-8.7 in your providers "physical" lineup. I see plenty of cable cos use crazy program #s and skip around, but usually when single-digit program numbers (i.e .8 & .9), there are channels filling out the multiplex. You OK with losing those too if you filter out 8 from your Cable Co?
- I don't know any all-in-one that will do what you want. The only devices I've seen that will let you groom the program #s specifically to 8 & 9 are encoders, muxes, edgeQAMs and groomers. Modulators usually don't, as that is not their function; they expect everything to be already encoded & tabled. But I can't think of any device that has an onboard 8VSB tuner that will do all that. I saw no mention of being able to specify program #s in any of the units above.

For all the money and effort you'd probably put in, it seems the most reasonable option would be to get an off-air DVR and hook it up to another input of through an Xbox. You could also check if another provider had your local in HD and the DVR features you'd want. Can you get the HD programming through a Tivo app?
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post #25 of 31 Old 10-06-2016, 01:50 PM
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You must mean that Cable EIA Ch8 has a Center Frequency of 183 MHz and EIA Ch15 has Center of 129 MHz: [You're missing a Zero.]
https://www.tonercable.com/pdf/CATV_..._Frequency.pdf

When you use the Insertion Filter [depends on the Filter Specs], it's likely to KILL EIA Ch7-10 and maybe also Ch22 [below Ch7 in EIA Plan]...cable channels can only sustain a Loss of perhaps 1-15 dB before they drop out, depending on what the level was to begin with. Likewise you will also KILL Ch14-17 and maybe Ch99 [below Ch14 in EIA Plan]. BTW: There are MULTIPLE PROGRAMS on each EIA Channel number, which are ALL going to be KILLED....

You would be better off KILLING groups of channels further up in Frequency, such as in a Tier NOT likely to be used. BUT, as AltAntMike pointed out, once or twice a year the Cable CO will probably reshuffle the deck, so be prepared to replace the Insertion Filters....esp. if they expand Multiple Channel-Bonded DOCSIS 3.0 Internet to the block you chose to use...which can be very difficult to KNOW since most DOCSIS 3.0 Channel-Bonded Cable Modems will ONLY display the 8 Channel Frequencies [some are 16] it is currently assigned to use and you will be left in the dark as to where all 32 [could be 16] Channel Frequencies are Assigned. Likewise, unless you are actually WATCHING Premium, PPV and VOD Channels, you have NO IDEA where those Frequencies are Allocated.

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post #26 of 31 Old 10-06-2016, 03:20 PM
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Quote:
Originally Posted by holl_ands View Post
You must mean that Cable EIA Ch8 has a Center Frequency of 183 MHz and EIA Ch15 has Center of 129 MHz: [You're missing a Zero.]
I had noticed that, too, but I didn't want to look like a Bozo if I was doing my arithmetic wrong.

Quote:
When you use the Insertion Filter [depends on the Filter Specs], it's likely to KILL EIA Ch7-10 and maybe also Ch22 [below Ch7 in EIA Plan]...cable channels can only sustain a Loss of perhaps 1-15 dB before they drop out, depending on what the level was to begin with. Likewise you will also KILL Ch14-17 and maybe Ch99 [below Ch14 in EIA Plan].
Hol_land's pessimism regarding the performance of the single channel elimination filters is excessive for the VHF high band. My initial concern was based on my thinking that the 8VSB to QAM house channels were going to be up in the range of where broadcast UHF channels overlap cable channels (about cable channels 65-125) because those are the cable TV output channels that agile, analog modulators usually are tunable to.

In the VHF highband, the grade of elimination filter you can buy for $500 will probably be speced with numbers referenced to the old NTSC days (here we go again with the shabby specs info) and will probably tell you that there will be X dB of attenuation at 179.75 MHz (channel 7 aural carrier) and "Y" dB of attenuation at 187.75 MHz (channel 9 visual carrier) and will be less than 5dB at each edge. Broadcast 8VSB (we seem to have settled on calling it ATSC here) signal "boxcars" are pretty robust and can easily survive that much deformity.

Just make sure that the elim/insertion filter passes up to 860MHz. You'd be amazed at how many that were produced by reputable companies that are only certified to pass up to 750 MHz, and even though the one I tested did pass up to 860 MHz, there was no way in hell I could risk installing it to insert a lobby camera picture into a franchised cable system, because the first time any cable TV tech was called out for any kind of a service call and saw it in there, he'd surely just yank it out and blame if for whatever the reported symptom was... just like they used to when we diplexed satellite TV signals into the cable TV home runs. You also may have to externally bridge the upstream, low frequency "return" path as well.


Quote:
BTW: There are MULTIPLE PROGRAMS on each EIA Channel number, which are ALL going to be KILLED....
Back in the analog days, cable companies used to put their lowest priority programing on channel 19 because of local broadcast interference, so you might want to see what is on that one right now. They probably similarly put junk on cable channels 95-97 as they are overlapped by the FM broadcasting band (88-108 MHz), so that, too, might be "cheap real estate" for your Eminent Domain authority to expropriate.

Quote:
You would be better off KILLING groups of channels further up in Frequency, such as in a Tier NOT likely to be used. BUT, as AltAntMike pointed out, once or twice a year the Cable CO will probably reshuffle the deck, so be prepared to replace the Insertion Filters....esp. if they expand Multiple Channel-Bonded DOCSIS 3.0 Internet to the block you chose to use...which can be very difficult to KNOW since most DOCSIS 3.0 Channel-Bonded Cable Modems will ONLY display the 8 Channel Frequencies [some are 16] it is currently assigned to use and you will be left in the dark as to where all 32 [could be 16] Channel Frequencies are Assigned. Likewise, unless you are actually WATCHING Premium, PPV and VOD Channels, you have NO IDEA where those Frequencies are Allocated.


- ANT
ennaALTernativesMIKE resembles that remark

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post #27 of 31 Old 10-06-2016, 04:50 PM - Thread Starter
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The adjacent channel issue is going to kill my plan. As I said C-SPAN is on the next closest frequency, so it would get wiped out or infringed upon as well. And as others have pointed out the cost has gotten outside the scope of what it is worth. I'm looking at a Tablo TV box at this point. I could use their Roku app to stream the channels to the other TVs where I don't have antenna drops available.

Just to answer some of the questions though:

My source for the channel map is two local users with HDHomeRun devices who were able to pull the entire thing off their boxes. Everything in our area is all digital, no analog, so channels are all over the spectrum.

In this case because the two channels I wanted to replace are in SD they're located with other SD channels on the same frequency. Thus losing the other channels broadcast on that same frequency, or digital channel in this situation wouldn't be an issue. BUT losing the adjacent frequency which carries a few HD channels would be.

The 183mhz center frequency came from the channel map. The two channels in question are broadcast on RF 8, 183mhz program #'s 8 and 9. So the way I interpret that they're sending it out on the equivalent of 8.8 and 8.9 based on the TiVo diagnostics screen. That's where those numbers came from.

However the cable box, or cable card in my case knows that 8.8 and 8.9 convert to 2 and 15 respectively.

If we put this in antenna terms, the first channel I wanted to replace would be real channel 8.8, virtual channel 2. The second would be real 8.9, virtual channel 15. (And yes, I know they don't work the same as OTA channels... just using that because it makes explaining easier)

There are the cheaper filters available though I'm sure they wouldn't work as well as the professional grade versions. I talked to the jan_jenca seller on eBay who assured me he could customize one of the filters to "block" what I needed to block for about $60. But he confirmed adjacent channels would be affected on both sides as well.

Thanks to everyone for the input. I think I am going to pick up one of the VeCoax modulators though to do as others have done and integrate my Apple TV with my TiVo. That would allow me to archive recordings that only are available via streaming providers.
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post #28 of 31 Old 12-26-2016, 07:45 PM
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ATSC to QAM Processor

AQP-2230
ATSC to QAM Processor

Converts ATSC signals into a QAM output

◆ 2U design
◆ Quick Boot-up
◆ Covers frequency range from 54 to 860 MHz
◆ 2 x RF inputs, 1 x RF output
◆ Remote control via supplied utility
◆ Local control via friendly front button control panel

--Taiwan Antex--
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post #29 of 31 Old 12-26-2016, 08:08 PM
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GDM-100D
HD Digital Encoder Modulator

Converts your HD Video Signals into a RF signal
For Business and Home theater

◆ Box type
◆ Integration of MPEG2 Encoder and Modulator in a box
◆ Covers frequency range from 100 to 860 MHz
◆ 1 x HDMI input, 1 x RF output
◆ User friendly configuration interfaces including LCD with buttons
◆ Best for Home Theater application

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post #30 of 31 Old 01-10-2017, 09:51 PM
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Has anyone compared THOR vs PVI? I am going to be completing a large TV setup and I'm not sure who has the better product. Thor seems to have a decent price on their 4 channel product (including IP stream) right now. PVI is a little bit more and doesn't include the IP feature.

http://thorbroadcast.com/sklep-205/produkt-220
http://www.pviusa.com/VeCOAX-PRO4-HD...ator_p_43.html
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