I am a new HDTV subscriber, however I am concerned about picture quality and the relation to signal strength.
Currently have the H20 receiver with 5 LNB Ka/Ku dish. Signal strength is ~ 71. Picture quality is so-so on non HD stations, OK on HD.
Before subscribing to DirecTV I had Dish Network and the picture quality was surprisingly good. The TV is a Panasonic 42" plasma.
I am new to this - satellite, signal strength, resolution, etc. Does signal strength correlate to picture quality. I don't think the dish was not fine tuned (aligned) when it was installed a week ago. I called tech support and they gave me the run around.
It seems a greater signal strength would have some effect on picutre quality. Any help will be appreciated.

No, it doesn't. If you have a watchable signal (no pixelization) then you have the highest quality you're going to get, no matter the signal strength. The only effect low signal strength has is reliability...in bad weather, etc. As picture quality goes, either you have a perfect picture, or none at all. That's how a digital signal works.

Thanks for the reply. However, as I am doing more research it seems there are other positions than what you propose.
Since the signal (even though it is digital) is sent by way of radio waves there is the possibility of noise distortion. There is a direct relation between signal strength, noise (signal interference) and data loss (bit error rate). So the higher the signal strength the less likelyhood of data loss because of noise distortion.
Even though it is transmitted in a digital format, it still can loose data that will effect quality.
If the noise distortion is great enough (to cause pixelization) then it is the receiver that actually malfunctions and is not able to project an accurate image onto the screen, because the signal is not strong enough for the receiver to do its job.

Signal strength, as I now understand it, is how well the dish is pointing toward the satellite and it does have an effect on the clarity, color, and sharpness of the picture.

I received this information from an electronic engineer who has worked on satellite communictions.

I am going to attempt to adjust the dish to obtain greater signal strength and will report back on the results.

Any impact on a digital signal's integrity will be visible in the form of very obvious breakup or pixellation NOT in analog-only terms such as "weaker color" or "soft sharpness".

For example, say I send a Word document to you and something happens along the way and it gets corrupted in the middle, but you can still open it to read it. What would you expect - the sentence "The red ball rolled down the stairs" to become "The red ball riiie233qmmderp the stairs" or "The red ball bounced up the stairs".

Because to impact picture quality the way you're suggesting would require that random digital distortion to still be completely legible to the receiver in order to NOT produce visible breakups. Sort of like putting 1000 monkeys into a room with 1000 typewriters and getting Shakespeare each and every time.

Daniel's exactly correct. Adjusting your dish will increase the reliability of the signal but not the picture quality.

Take ATSC (digital over-the-air) for example. 50% signal strength on a digital channel looks perfect, while 50% of an analog signal strength would look pretty snowy, I'd bet. However, you are more likely to have a 50% signal drop out than a 100% one.

An analog effect, nicely countered by digital signal methods. Not noticeable until failure occurs.


Nicely handled by error correction. Not noticeable until failure occurs.


Yes, but you won't see any difference unless the low signal causes complete failure.


Yes. Until quality is affected by what is sometimes referred to as "going over the cliff," picture quality will be perfect. Going over the cliff is having all transmission problems finally add up to the point where the digital signal is not transmitted properly. At that point the signal does not degrade, it falls apart. Large areas of the screen showing 1/2" or larger squares of solid color, or images freezing; these are failures. Until such a failure happens, the delivered image is identical to the image delivered under perfect signal conditions.



A receiver that displays a pixelized image because of low signal conditions is not malfunctioning. It's supposed to show a bad image when the signal has failed.


The receiver doesn't actually project an image onto the screen. It supplies an electrical signal to allow a display to do that. You may say I'm being picky, but this sentence shows some fuzzy thinking on your part.


Signal strength is a misnomer on satellite receivers. They actually show signal
quality," an undefined thing that only guarantees that if it is low enough, the image will not come through properly. A client once insisted I add a 10 dB amp to his satellite feed; it distorted the signals, and even though they were 10 dB hotter, the satellite receiver showed a lower "signal level." What happened was that distortion made a lower QUALITY signal. Incidentally, some stations came in fine and some were ruined by this stronger distorted signal. Raw signal strength itself is not a predictor of performance.


Ask him about what I wrote, too.


You should do that just on general principles. A signal "level" of 71 is barely good in low humidity conditions, and pretty much guarantees signal loss in rainy conditions. Pay attention to the tilt of the dish, too, as the LNBs must line up with, essentially, the ecliptic. That means that in California, dishes are set some 12 degrees counter-clockwise of straight up, but as you move to the east, the dishes will be set more and more clockwise from that position. (I did not give total numbers of degrees as the old dishes call upright ninety but I think the new dishes call upright zero.)

sacpapa, I have pointed many DirectTV dish in this area as this is where I live. The signal strength of 71 is quite good for around here. Since Sacramento is flat all you really have to worry about is foliage. What is clear now may not be in Spring and Summer. When I pointed a dish I had the luxury of a Birddog signal meter which powered the LNB while I was right there adjusting it. Since, I'm guessing here, that you will be using the receiver as your meter, I recommend putting all your efforts into SAT 101. This one is the lowest on the horizon, as well as, in the middle of the five sats. (lol at myself) I can't tell you how many times I've had to raise a dish mount about 5 feet up in order to get 101. Again Sacto is flat but in the surrounding communities like Folsom, Eldorado Hills, Fairfield, Los Lagos gated community, you know where there's large bumps on the ground, it's a different story. Since you already have "decent" signal levels you should not have to move very much. It is possible that you may have to degrade a sat signal in order to bring a lower one up, mainly 101. So if you concentrate on 101 and the tilt is correct the other 4 can only be better. Good luck and don't forget to come back and let us know how it goes. Lots of nub's seem to forget that last step so we're left wondering?????????

Greetings and thanks for all the input, I greatly appreciated it.

Ernie, I especially appreciate your line by line responses, they are very helpful. And thanks for clearly up the fuzzy thinking, I understand what you are saying.

Also, if I understand you any distortion (noise) that happens it is corrected by an error correction process...

I did readjust the dish yesterday and was able to bring it up to 74, but will have to wait to see how it operates in rainy weather.

Thanks Mitch for the tip on adjusting at the 101 sat. It is a little confusing trying to adjust for all five, although I noticed on one blog someone said that 99 (I believe it was) is not yet operational.

I still have some concern about the adjustment for the Ka sats, since one video instruction I found mentioned that the peak is much smaller than the Ku peak for tuning. To be honest I don't know which sats supply which programming. I would simply like to try to tune this as well as is reasonably possible since we invested quite a bit for the new TV.

sacpapa, here's some previous discussions that we had that may help shed some light.

[Link: remotecentral.com]

[Link: remotecentral.com]

[Link: remotecentral.com]

Also, do you know which H20 receiver you have?
Does it have a bevel where the front meets the top of the box?
or is it a flat front all the way to the top?
The reason I ask is that the beveled front ones get very hot so keep it away from other heat sources if possible, or you may have heat related issues down the road.
Such as, total signal loss while watching tv so that it has to re-establish a connection and download the guide again.
The flat front H20's are the 100 series as mentioned in one of the threads above. These are better and have less issues since they barely get warm. The 100 series H20's do have a sticker on the back that say's H20-100.

Thanks again Mitch, the info is most helpful for a first timer to dish intallation.

I have the H-20 with the beveled front: manufactured 10/20/06, the level indicates. I will keep an eye on the heat levels.

When I readjusted the dish a couple of days ago the mount was not level, and I was not able to bring it to a level position because it hit the roof tiles (the dish is mounted on top of a six foot fence that attaches to the side of the house). So I attempted to readjust tilt, elevation, etc. without the mount being level initially.

Now that I have the full set of instructions in hand (thanks to the previous thread), I am considering moving the dish a few inches so I can begin from a level mounting position. However, I have a QUESTION. Can I use the "customer's receiver" to do the "course alignment" as well as "fine-tuning" the tilt, elevation and azimuth? Since I do not have an "in-line" meter using my receiver is my only option at this time.

Excellent decision.




Yes it can be done.
You need a compass to point the dish to the southwest, once you have the dish set to the proper specs.
The specs are provided by the manual and the settings from the receiver when you input the zip code from the area of installation.
Hook the receiver to a tv and turn it on to get the preinstallation instructions.
It does not have to be hooked up to an LNB.
You only go as far as inputting the zip code then it spits out the proper degrees to set the dish up with.
This will do well for course alignments as that is all I've seen (some) DirectTV guys do and call it good. (Not all of them)
As far as fine tuning, put on your track shoes and be prepared to move small increments and run back to the tv to check your signals.
Or turn up the volume to listen for the audible signal meter built into the receiver.
You should do well with just the course settings.
Being a nub you will try fine tuning this way probably only once.
It is a necessary evil, it's part of the learning process.
Knowledge is expensive, failure is free.
Oh wait, that sounds familiar.

Anyway, sacpapa good luck and come back again.