Can't get all OTA DTV channels on Magnavox tuner

[spikyspikyspiky]

(aha, finally found the post thread button!)
My Magnavox H2160MW9A HDD&DVD recorder unit includes a DTV (OTA) tuner. I live in LA so there are a lot of powerful DTV Over The Air stations.
But my apt building also provides free basic Time-WArner cable tv coming out of the wall. (Channels 1-99 are included with our basic building service; if I sign up and pay Time-Warner more, I can get the ones above 100.).

The Magnavox unit can handle both: there's a DTV/TV switch on the remote. In DTV mode, it's using the tuner OTA. In TV mode, it's showing me the channels on the cable.

I like some channels that are only on cable but when it comes to wide-screen network channels (KNBC 4, KCBS 2, etc), Time-Warner truncates the pictures, cutting (not squeezing) it down to "pillar box" - e.g. when there's a wide shot of 3 news anchors at a desk, I see the middle guy, but half the face of each guy sitting on either side is chopped off. The cable company told me for correct widescreen pictures, I should tune to cable channel 402, 404, etc, for which they want me to pay extra. Also, I just prefer a lot of the local OTA channels with the older shows, which I don't think are on cable at all.

So I just switch the Magnavox to DTV mode and there, the OTA channels (KNBC 4.1, KCBS 2.1) are correctly appearing as complete, widescreen images. BUT unfortunately only a few of the OTA channels come thru! And Magnavox Helpdesk said I really shouldn't even see any of those when the Time-Warner cable is attached (she apparently didn't know the unit has two modes)! Instead, she said to get OTA I need to unplug the cable and plug in an antenna instead. Using an antenna does get me more OTA channels...but of course then I've unplugged my cable channels. Which is kind of the point of having a unit that can switch back and forth (especially when using the DVR recorder -- the timer program lets you choose DTV or TV as well as the numbered channel and time. So e.g. I can schedule to record an MSNBC show on cable 49 as well as an OTA CBS 2.2 OTA broadcast, without being home to mess with wires or switch modes.)

I guess my problem boils down to, the tuner only seems to get a few of the OTA channels as long as the T-W cable is connected. And there's not a separate antenna input on the back -- they assume you will want EITHER cable OR an antenna as the input. Even though the unit is so clever and can switch between the two.

can anyone suggest a way I can expand the reception of the DTV tuner to get more of my area's OTA channels... without having to give up my cable connection? I mean, is there such a thing as a Y-adaptor that I could effectively plug both an OTA antenna AND my wall cable into the unit...? and would the unit still be able to differentiate do you think. Or would it blow up?
;-)

appreciate any hints you can offer. I have searched a lot and this is the only forum I found where anyone seems to really know what's what regarding DTV issues.

-Alan

[lordsmurf]

First verify that the picture settings are 16x9 everywhere on the DVD recorder.

Your frustration is likely due to an ATSC/QAM issue. The cable company is only broadcasting the SD version over their QAM frequencies. Your Magnavox DVD recorder can only understand OTA (antenna-based) ATSC, or cable QAM (clear unencrypted QAM).

Yes, you can plugin in two coax connections, using a splitter. But not just any splitter -- get one that is at least 2Ghz (2000Mhz).
This is a good one for $14: http://www.amazon.com/gp/product/B00...SIN=B000Y97Q86
You won't easily find good splitters in local stores -- not even Radio Shack, Lowe's, Best Buy, etc.

Not to be crass, but the person you spoke to at Magnavox was an idiot. Ignore everything he/she said.

You'd likely have the same problem talking to anybody at Time Warner. However, that's really quite expected. Basic support and sales support employees read from scripts, or are only allowed to parrot the company line -- even if they know better, as many installers do. Concepts such as ATSC and QAM are lost in this process. Their underlying goal is to always sell your something higher. I've had that issue with Charter and Comcast.

Cable companies have hidden most of the information regarding DTV/HDTV, as a lot of them were opposed to it -- the whole industry's trade group, in fact. (Reference: White paper.) Several were outright deceptive and unfair to their customers, using the DTV transition as a scare-tactic way to upsell their customers into pricy all-digital/non-analog services.(Reference: ABC News story.) A lot of this still goes on, in relation to cable and local channels. The con these days is to split the HD from the SD, and upcharge you for the HD version -- something I had thought was illegal, or was going to be, but that's not the case from what I've seen.

To better understand some of what's at play here, also read these threads/articles:

• http://www.digitalfaq.com/forum/home...s-require.html
• http://www.digitalfaq.com/forum/vide...mputer-tv.html
• About the must-carry FCC regulations: http://en.wikipedia.org/wiki/Must-ca...tal_must-carry

[lordsmurf]

Quote:

Originally Posted by spikyspikyspiky

Hi, you wrote helpfully last year about this DVR/tuner (i would add to that guy's old thread, but it said I shouldn't, and now I can't see how to post a new thread at all!) ... You seemed quite savvy in your other posts. =-) can you think of a way I can expand the reception of the DTV tuner to get more of my area's OTA channels... without having to give up my cable connection? I mean, is there such a thing as a Y-adaptor that I could effectively plug both the OTA antenna AND my wall cable into the unit...? and would the unit still be able to differentiate do you think. Or would it blow up? ;-) ... appreciate any hints you can offer. I have searched a lot and this is the only forum I found where anyone seems to really know what's what.

Just wanted to share this portion of your PM. Thanks very much for your kind words.

[spikyspikyspiky]

thank u your lordship. I figured combining the two feeds into the one input was worth a try so i grabbed a "diplexer" at Radio Shack (which the guy said would combine the coax cables as I desire) but it's only 75 Ohm, so I'm guessing not as good as what you recommended (should I just wait till the one you mentioned arrives?). And just to confirm, yours works as a "combiner" even though it's called a "splitter," right?

Also, just to confirm: once I have both the OTA antenna and my Time-Warner cable co-mingling into the Magnavox tuner box, the two won't somehow interfere with each other's signals, or confuse the Magnavox, will they?

If I got it right, OTA is an entirely different kind of signal (ATSC, if i understood you) from cable tv's signal (QAM, yes?) and that must be what the Magnavox is differentiating between when I click "DTV" vs. "TV"... so Magna will just ignore or filter out the other kind of signal coming thru the input...? Or is there some other magic here? I guess I'll know if suddenly I have nothing but a mishmash coming through.

(I totally agree about the tech staff at the companies -- they just blithely tell you you need an upgrade. One T-W lady told me that if the widescreen broadcast was truncated on the sides, I should just use the picture stretch option! So first they chop 2/5ths of my picture off the sides, and then tell me that any actors who do remain onscreen must be transformed into obese dwarfs.)

Thanks for the article links. The cable feed in our ancient apt building by the way is not Fios or U-verse. But it's interesting to think the cable ought to be carrying the proper signal, not the chopped off picture, from the local stations. But even if T-W complied, must-carry still wouldn't get me the other DTV OTA stations that are so fun, would it? I mean like 5.3 and 56.4 and so on, where the oldy tv shows and movies hang out (ThisTV, AntennaTV, MeTV). Those are the real reason I want to boost my tuner with an antenna. I'm guessing the few OTA stations I do get (while the cable is the only thing plugged in) are just the ones who are so strong that the tuner picks them up without any antenna...! or am I misunderstanding how that works.

Thanks again for your patient and clear explanations!

[dad2]

LS,
I have the same situation with my TV and Philips DVR setup. That is a good splitter you recommended, but it has just one input and two outputs. I don't understand how it can combine two seperate input signals to output too the TV's one antenna/cable input terminal. Can it work both ways, meaning can it be reversed by using the output connectors as inputs and its one output as an input terminal? It would be a help if it would! I have though of buying one of those dual-input remote-controlled A-B antenna/cable switchers, I think I saw them listed on Amazon.

[lordsmurf]

Quote:

Originally Posted by dad2

Can it work both ways, meaning can it be reversed by using the output connectors as inputs and its one output as an input terminal?

Yes.

It's not monodirectional -- it's passive bidirectional.

Just be warned that sometimes combining the two signals results in some sort of collision or crosstalk, and you'll lose some channels. I used a setup like this at home a few years ago, and the LCD EDTV received both ATSC antenna and digital cable (through the box) just fine. That TV didn't have the ability to receive QAM, so no idea if it worked. It probably did. Three years later, I tried the same setup on another LCD HDTV, using the same cable box, and it received the DTV/ATSC antenna stations and analog cable channels -- but not the QAM, and the digital cable box received nothing.

So it's not 100% reliable, but it can work. In fact, that one time I had a problem was the only time I've seen it fail in probably 20 years of using splitters.

[lordsmurf]

Quote:

Originally Posted by spikyspikyspiky

"diplexer" at Radio Shack (which the guy said would combine the coax cables as I desire) but it's only 75 Ohm

Ohms are a difference measurement from Mhz. All TVs are 75 Ohm that I know of. I remember the late 1970s TVs all have 300 Ohm twin leads, and lots of 1980s products shipped with 75 Ohm baluns. I remember when we got a new TV in the early 1980s, and had to buy a special adapter for the Atari 2600 and our Pong system.

A diplexer is not a splitter. A diplexer is a special kind of splitter that is used in specific scenarios. For example, to split satellite signals from the LNB (dish) to multiple receivers. Diplexers can also be used for cable boxes in some situations. You never use a diplexer when a splitter is the required wiring.

Side rant: Not to be crass (again), but the Radio Shack guy was also an idiot. Radio Shack today isn't Radio Shack of the 1970s and 1980s. Most of them are clueless twits, and I sometimes wonder if it's a corporate policy to always have answers for customers -- as opposed to an honest "Sorry, sir/ma'am, I don't really have the answer for that."

Quote:

so I'm guessing not as good as what you recommended (should I just wait till the one you mentioned arrives?). And just to confirm, yours works as a "combiner" even though it's called a "splitter," right?

It's a passive split, meaning it works bidirectionally. Two signals into one, or one signal into two.

Quote:

If I got it right, OTA is an entirely different kind of signal (ATSC, if i understood you) from cable tv's signal (QAM, yes?) and that must be what the Magnavox is differentiating between when I click "DTV" vs. "TV"... so Magna will just ignore or filter out the other kind of signal coming thru the input...? Or is there some other magic here? I guess I'll know if suddenly I have nothing but a mishmash coming through.

Mish-mash.
ATSC is a video standard, which also includes broadcasting specs. With private transmissions systems -- i.e, cable and satellite -- only the video standard applies. The broadcasting is moot. Cable/satellite broadcasts with a mix of DVB variants, QAM, and others. Granted, I'm oversimplifying here, but it's a good enough explanation. You're essentially receiving ATSC format video over QAM. QAM is just a modulation for sending signals.

A jargon-heavy version is here: http://en.wikipedia.org/wiki/ATSC_%2...d_transmission

Quote:

just use the picture stretch option!

I would rather not watch TV than see something distorted. Sorry, but I'm not blind.

Quote:

But even if T-W complied, must-carry still wouldn't get me the other DTV OTA stations that are so fun, would it? I mean like 5.3 and 56.4 and so on, where the oldy tv shows and movies hang out (ThisTV, AntennaTV, MeTV).

Sadly, no.

I'm too far away from the antenna array where I am, and cable doesn't carry it. So I'm sadly unable to watch the lower-power DTV channels like ThisTV, RetroTV, etc. Fellow TV show collectors, friends and family are always talking about these great new channels they get, but I get nothing. I'm one of those people who didn't really benefit from the digital transition.

[spikyspikyspiky]

cool. I will wait for the 2GHz splitter/combiner.

Meantime, I did some scientific testing (without combining) of
(1)just the T-W cable, and (2)just the antenna.
Takes awhile to let the tuner re-scan the spectrum every time I switch!

But it seems my antenna doesn't receive much anyway (basic RCA $5 type, with rabbit ears plus a UHF loop) . Certainly not the 56.3 etc subchannels I was hoping for -- and not even some of the major OTA stations that do come thru when the cable is attached! (such as NBC 4.1, CBS 2.1). I'm theorizing that the strung out cable itself is functioning as a kind of antenna, apparently more effective for the big OTA network stations. How else could this "improved" reception vs. the antenna be explained?

in short i get:
(1)With cable only: all cable channels PLUS DTV 4.1, 5.1, 7.1, and a number of other major OTA digital senders. But no 5.3, 56.2 etc.
(2)With antenna only: no cable of course, BUT only a few of the above DTV channels and still no subchannels. Maybe I didn't put the antenna in the best position.

I am only 15 miles from where all these channels originate. I can almost see that mountain from my 5th floor balcony. However, I'm inside a large apartment building. AntennaWeb says in my location for the channels I want, a simple, unamplified antenna should suffice (but isn't that the one I already have?). And they did say amplified might even be counterproductive.

Do you have a recommendation for a better antenna in my situation? And how to point it?

=-)

[lordsmurf]

Use this antenna: http://www.amazon.com/gp/product/B00...SIN=B0017O3UHI

It's a $100 currently on sale for $65 shipped.
You can hang it on an interior wall, or you can put it in the attic. It will get channels from 30-40 miles away.

I helped family select and install this in their living room a few years ago, and it's been perfect.

Here it's called the CLEARSTREAM2 Antenna, but it has several others names. It used to be available at Best Buy for $110, under another name.
It's a Terk -- a name brand most people don't know, but they make and sell quality video transmission product.

I'm about to buy one for the attic.