NEED HELP- direcTV HD dish installation gone wrong

[1 FMF]

well not really, not yet hopefully.
With High definition service, you need the oval dish with multiple LNB's. I have that, 3 LNB's to be exact. Now, the installers came out today (Sunday), I won't describe them because it'll violate board policies and I'll get banned. I anticipated all this and planned on doing the installation myself but we had to wait for the installers because they were the ones bringing the dish. They did not leave a multi-switch. Do I need one? How do I get from the HD receiver (coaxial input from satellite) port to the correct LNB on the dish? There are 4 ports on the dish, and I thought for HD you need to pick up multiple satellites, if not then which port do I use?

They were also supposed to bring an off-air antenna. It was ordered and on the receipt, and after explaining that, they didn't bring one and said we'll have to ship it to you but said they don't work that well and to go with a terk.com antenna and cancel the antenna we ordered. So in calling best buy to get a refund because we never received it, they say call DirecTV. The credit card charge was actually by directv for this but they say to call best buy, and the fun begins.

 

[ALS]

I have a Direct TV dish and absolutely love it.
The installer was great to deal with. Two friends that also got a dish with in a month of me also could not believe how nice and professional the installers were. I would call direct TV tomorrow and ask for a different team of installers. These guys at least by me here in Pittsburgh are independent contractors. I would guess your installers worked for Best Buy and have an attitude. Go over Best Buy's head and talk to Direct TV's customer service. They should make it right for you.

 

[1 FMF]

yeah, directv service is great- after it's installed. It's the installation thats the pita.

Anyone know of a link to detailed dish connection instructions? I tried looking up some, and came across a terk dish with triple LNB's and 4 coax ports. It's not my brand dish but looks the same, and theirs said simplified install and good for up to 4 rooms without additional hardware (as in multiswitch?). So I'm hoping that's sort of what I got and can use any port to the HD receiver.

 

[keith]

If the Terk they recommended is the circular style that clips on to the dish (e.g TV44), it may or may not be a good choice. The Terk will be pointing in the same direction as the dish. If your OTA channels are on the same path as the satellite, it will work. If not, you may be disappointed.

Installers ought to know this stuff, so maybe they know that the Terk will work well for you. Go to Antennaweb and see where your OTA's are, and compare to the dish orientation:

Antennaweb

 

[Win]

quote:

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Originally posted by 1 FMF:
well not really, not yet hopefully.
They did not leave a multi-switch. Do I need one? How do I get from the HD receiver (coaxial input from satellite) port to the correct LNB on the dish? There are 4 ports on the dish, and I thought for HD you need to pick up multiple satellites, if not then which port do I use?

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Welcome to the HD club!

No, you do not need the old style multi-switch with the new 3 LNB dish. Just connect from any one (or two) of the ports on the dish to one (or two) of the sat inputs on your HD receiver.

edit: The receiver/dish combo are smart and automatically handles all the LNB switching. It is the combination of the oval dish and the tilt of the antenna that allows the dish to "see" all of the necessary satellites at one time.

The over the air antenna connects directly to your HD receiver and does not go through the dish at all. edit 2: I just use a set of rabbit ears - the digital subcarriers are transmitted at very low power relative to the main analog channel, but as with all digital signals, either you get it perfect, or you don't get it at all .... none of the snow, multipath, or other stuff associated with an analog NTSC video signal.

The small directTV dishes are easy to install; once you get the bearing to the sats, there are indicators on the mount for azimuth and tilt - it's really pretty user friendly for rocket science ....

[ June 06, 2005, 07:32 PM: Message edited by: Win ]

 

[keith]

quote:

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Originally posted by Win:
... I just use a set of rabbit ears - the digital subcarriers are transmitted at very low power relative to the main analog channel, but as with all digital signals, either you get it perfect, or you don't get it at all .... none of the snow, multipath, or other stuff associated with an analog NTSC video signal.

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The 8VSB modulation scheme used for ATSC OTA is very prone to multipath, which manifests as dropouts in both the audio and video. A more directional antenna usually helps. The Terk clip on antenna is described by them as 'multidirectional'. It looks like a folded dipole, which is the most sensitive to multipath.

If the installers are familiar with your area and they know that antenna is sufficient, it is a neat solution. I have a monster ChannelMaster 3020 and get 5 decent OTA digital channels, but ABC has dropouts. It's true that you won't see analog type snow or ghosting on the digital OTA's, but dropouts are plenty aggravating. Adding an amplifier does nothing because it's a multipath problem and there is already plenty of signal. Too much of the wrong kind of signal mixed in there too.

The 5th generation LG tuner chipset is supposed to be the best performing in the presence of multipath. I might buy a FusionHDTV 5 PCI card to see if that helps my ABC channel, and sell my FusionHDTV 3. If you are lucky enough to have strong OTA signals with little multipath, you'll never know about these 8VSB problems.

 

[Win]

By 8VSB, I presume you mean "vestigal sidebands" that are carrying the extra digital information as subcarriers on the analog channel.

I guess I don't understand the mechanism that would cause the digital signal to drop out from multipath interference.

In the analog amplitude modulated NTSC video signal, multipath typically manifests itself as video ghosting, because of the time delay between the primary signal and the reflected signal.

With the digital signal, a time delayed data packet is simply redundant information, assuming you would not be so unlucky as to have a data packet arrive at the exact same instant 180 degrees out of phase so as to cause a complete signal cancellation.

Are you sure that you are not simply seeing the effect of a marginal signal or high RF noise floor if you are using a pc computer based tuner, and not multipath? A directional antenna would have some gain relative to a set of rabbit ears or other dipole type antenna that would improve reception with respect to a marginal signal.

 

[1 FMF]

I ask about a switch and connecting one coaxial cable, and the responses I get are vestigal sidebands, carrying extra digital information as subcarriers on the analog channel, and analog amplitude modulated NTSC video signals

Thank goodness I'm not hooking up the flux capacitor and switching to channel 88

thanks for the confirmation on the dish hookup. Will hopefully be installing it on the roof tomorrow night, the commdeck roof mount should arrive ups tomorrow.
As for the OTA channels with an antenna, I think I'm going to get the terk, or similar directional antenna. The dish is pointing 232 deg (SW) and the channels we want are the NY stations- ABC, NBC, CBS, FOX, which according to antenna web are 233-238 deg and 55-60 miles out. We are at the highest point in town, zip 06468 monroe ct, and used to be able to see long isl sound 15+ years ago before the trees grew, so I'm hoping the terk clip on will do real well. Should be no source of multipath where the dish is getting mounted either. And for what it's worth, I understood most of the signal jibber jabber, I do radar stuff for work

thanks again.

 

[Win]

A good primer on the over the air 8VSB digital transmission system!

http://www.zenith.com/sub_hdtv/hdtv_papers_atsc_system.html

 

[keith]

quote:

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Originally posted by Win:
By 8VSB, I presume you mean "vestigal sidebands" that are carrying the extra digital information as subcarriers on the analog channel.

I guess I don't understand the mechanism that would cause the digital signal to drop out from multipath interference.

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The V in 8VSB is a little misleading because it is required:

WHAT EXACTLY IS 8-VSB ANYWAY

It saves bandwidth over traditional DSB. Regular analog OTA also uses VSB.

Without going into too much detail, multipath interferes with the orthogonality of the signal and the receiver can not differentiate between desired and multipath components. The receive eye closes and the receiver starts to create bit errors.

Multipath performance is one of the major weak areas of 8VSB, both theoretically and verified experimentally:

SPECIAL POSITION PAPER ON INDUSTRY RECONSIDERATION OF DTV MODULATION SYSTEM

 

[Win]

quote:

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Originally posted by keith:
Without going into too much detail,

(snip)

The receive eye closes and the receiver starts to create bit errors.

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Yeah, closing of the data eyes is explained in some detail in part 10. Equalization, of the Zenith paper, linked above.

It still looks like this is a system that is robust in terms of redundancy and forward error correction and that a multipath signal will not ordinarily be of significance to the data decoding.

Thanks for the other links to 8VSB data, it's certainly an interesting subject and I'll look at them.

 

[keith]

quote:

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Originally posted by Win:
Yeah, closing of the data eyes is explained in some detail in part 10. Equalization, of the Zenith paper, linked above.

It still looks like this is a system that is robust in terms of redundancy and forward error correction and that a multipath signal will not ordinarily be of significance to the data decoding.

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I only have one channel that suffers multipath, but then again, it's pretty rural where I live. Urban performance must be quite hit and miss.

There was a long article last year in one of the audio/video magazines about a reviewer trying to get 8VSB reception in a Manhattan apartment. They had so much signal strength they didn't need an antenna, but due to multipath, they couldn't get reception with or without an indoor antenna.

I don't really care too much about my lousy ABC reception, especially now that Monday Night Football has moved to ESPN next season. In fact, ABC is the only major network NOT carrying the NFL next season. There is nothing on ABC that I want to watch.

 

[JohnBrowning]

IF you like HD DIsh NEtwork is the way to go not only do they have some HD channels but they are buying VOOM as well. Discovery is the best HD channel it almost looks like 3D on a good HD tv! Try to stay all digital and toss the coaxial cable away!

All dish installatioons are hit or miss due to the heavy out sourceing and multiple layers in the logistic chain! Lots of sub-contractors!!! Direct also does not pay their installers as well as Dish does so a lot of new hires and dead beats work for Direct TV. Do not get me wrong their are a lot of great guys that work for Direct TV but most end up working for Dish Network sooner or latter if they are any good!