Snow fade in Dallas? In March?

[spartanstew]

OK, so it's snowing here in Dallas. A wet, slushy snow.

I went to watch some live TV after the wife went to bed and was getting a Searching for Satellite 771 on just about every channel (both tuners - both HR21's). I very rarely get rain fade, but figured this must be snow-fade. I noticed, however, that some stations were coming in.

Then I realized, the stations that were coming in were all SD. I adjusted my guide to show all channels and was able to tune in ESPN SD and am now watching the Texas Tech vs. Kansas game.

I get a 771 when I try to watch the HD version.

Why is that?

[GAM]

Same here.

[lmelamed]

Same here.

[rjay717]

Cleaned off the dish and everything is back for me.

[spartanstew]

Cleaned off the dish and everything is back for me.

Maybe I can wake up my wife and see if she'll climb the ladder onto our 3 story pitched roof and clean mine off. :lol:

[mfrost]

Same problem here. All of my transpoders are reading 0 with the exception of a few SD channels.

[Greg Alsobrook]

Maybe I can wake up my wife and see if she'll climb the ladder onto our 3 story pitched roof and clean mine off. :lol:

!rolling

good luck with that!

[Supervolcano]

OK, so it's snowing here in Dallas. A wet, slushy snow.

Then I realized, the stations that were coming in were all SD.

I get a 771 when I try to watch the HD version.

Why is that?
The wetter the snow, the more problems the snow will cause.
The lighter the snow, the less problems the snow will cause.
Just like a heavy rain storm vs light rain storm.

And the Ka bands (99 & 103) are affected more than the Ku bands (101, 110, 119) because the slope of the curve is far steeper on Ka bands.

This means when your "peaked" (at the top of the curve) on all satellites, they should all have relatively the same signal strength, like above 90% or so. But when the Ku signals drop off the top of the curve down to say 75% strength, your Ka signals drop off the top of the curve down to probably 50%.

Pixilation begins when signal drops below about 40%.
Signal Loss begins when signal drops below about 25%.

[texasbrit]

I watched the signal here in DFW on the various transponders as the snow got thicker last night. The first one to go to zero was 110, surprisingly. At that point 101 and 119 were about 80s (normally mid-90s to 100) and the Ka signals had dropped off to about 40. About a half- hour later, with the snow coming down hard (very large snowflakes also) the Ka signals were down at zero. There was very little accumulation on the dish. 101 and 119 held up for most of the night although the signals were down at 50 or less and so there was considerable pixelation.

[dhammis]

One thing I've noticed is the MPEG-4 channels are *way* more vulnerable to rain fade, snow-fade, etc than other channels. The thing that disturbs me is when the switch happens and everything goes HD then cable commercials will be true about the signal quality issues. Is it a power issue on the satellites? (i.e. once they drop the SD broadcasts and can use bandwidth and power to fuel more HD broadcasts will this go away)

[hdtvfan0001]

I can't speak to the weather in Dallas, but in my area, we have had 2 occurances recently (one last week, and the other today) over severe rain and thunderstorms.

In both cases, no effects of rain fade have been seen. In fact, it is pouring cats and dogs right now and I am viewing my HR21 at this moment via my Slingbox access, and it has been solid all morning on 3 differetn channels.

Since there are so many factors going into a solid signal (Dish alignment, connector integrity, cable lengths and routing, multiswitch integrity, and others), it can be challenging to accurately diagnose reception "issues". There is not simple or single answer, as the installation environment in each location varies.

Having lived in a snowy climate for the first 8 years with DirecTV, I rarely saw any effects there as well. If snow is piled up or collected within the dish area or on the LNB's it can reduce the signal levels to create lowered reception.

[Redlinetire]

The wetter the snow, the more problems the snow will cause.
The lighter the snow, the less problems the snow will cause.
Just like a heavy rain storm vs light rain storm.

And the Ka bands (99 & 103) are affected more than the Ku bands (101, 110, 119) because the slope of the curve is far steeper on Ka bands.

This means when your "peaked" (at the top of the curve) on all satellites, they should all have relatively the same signal strength, like above 90% or so. But when the Ku signals drop off the top of the curve down to say 75% strength, your Ka signals drop off the top of the curve down to probably 50%.

Pixilation begins when signal drops below about 40%.
Signal Loss begins when signal drops below about 25%.

I'll agree that the 'wetter' the snow, the more signal is blocked.

But the fact that the Ka has a 'peaker' signal when physically aligning the dish is not related to how it performs due to weather interference.

[Supervolcano]

One thing I've noticed is the MPEG-4 channels are *way* more vulnerable to rain fade, snow-fade, etc than other channels. The thing that disturbs me is when the switch happens and everything goes HD then cable commercials will be true about the signal quality issues.
This is why peaking your dish properly is so critical now, more than ever.

I despise like the idea that directv only requires that an installer get 70's for strength. By this point they should KNOW that 70's on a clear day for Ku bands are going to cause utter hell for the Ka bands when there's even the slightest of moisture in the air.

Before they could get away with the 70's, but not any more.
They need to rewrite that rule for slimline installations.
And demand that installers get 90's for most transponders.

But I will say there ARE other things you can do to "help" your dish. I spray a product called "Rain Shield" on my dish ($30 per can at solidsignal.com). It does help, and it's designed for thin plastic (like the lnb heads). That's why it's so much more expensive than Rainx (which should never be used on the lnb's). It even helps in the winter as most of the snow will slide off quicker and/or not stick to it in the first place .... unless it's that real wet snow like this thread is discussing.

For winter, some people tie a thin plastic bag over the dish (not the lnb heads). Snow will have a tough time sticking to that since it will pretty much be vertical and will flex a little in the wind. The signal will still go through a plastic bag.

Is it a power issue on the satellites?
No, it's more like the wavelength of the transmission (or something like this).

Ka band will always have a "steeper slope" than Ku band.

This is why Ka birds can be parked 2 degrees away from each other while Ku birds need 9 degrees of seperation.

(i.e. once they drop the SD broadcasts and can use bandwidth and power to fuel more HD broadcasts will this go away)
If someday that occurs 10 years from now, and they broadcast mpeg4 signals from the old Ku birds (which they CAN do), it's just the channels coming from the Ka birds that will suffer from the steeper slope.

[Supervolcano]

I'll agree that the 'wetter' the snow, the more signal is blocked.

But the fact that the Ka has a 'peaker' signal when physically aligning the dish is not related to how it performs due to weather interference.
Huh?

I mean when the dish is peaked (in good weather) all sats (Ka and Ku) will have very high readings.
As the signal degrades (from bad weather), the Ka signals will fall off that signal slope a lot quicker than Ku signals.

What did I say that was wrong in that?

[shocky]

Just SW of DFW by about 30 miles.. No fade here last night.

[jgriffin7]

Northeast of Dallas, and lot's of fade last night. So glad I have an HR20 and was able to just switch over to the OTA tuner. Now, for the HR21 people...

[Redlinetire]

As the signal degrades (from bad weather), the Ka signals will fall off that signal slope a lot quicker than Ku signals.

What did I say that was wrong in that?

What I'm asking is how did you arrive at that conclusion?
What is that based on?

If the satellite is properly anchored and peaked, snow on the dish (in my experience) affects either signal equally. The width of the signal doesn't matter when the dish is anchored and not moving.

However I could see where atmospheric interference/noise (i.e. rain clouds) would affect the narrower beams more, based on what I've read here on DBSTalk. Thus it's critical peaking those signals as much as possible.

[eakes]

Rain/snow fade occurs because the size (diameter) of a water droplet approaches one wavelength of the RF frequency. Going higher in frequency (shorter wavelength) increases the rain fade effect. Thus rain fade is greater in the Ka band than in Ku.
Water droplets in rain clouds create more rain fade than does local (near vicinity of antenna) heavy rain. I have seen situations where the satellite signal fades out, but it is not raining at my home. The cause is storms passing to the south with extremely tall thunderheads. Conversely, it can be raining 'buckets' at the house, but no fade because the southern sky is clear. Snow fade is normally snow accumulating of the dish and feedhorn, especially the feed horn.

Proper alignment of the dish to get the maximum signal possible helps alleviate fading problems, but cannot prevent outages in severe conditions.

Since both Ku and Ka signals are received on the same antenna is absolutely necessary to peak the signal on Ka since it is more sensitive to rain fade and is the most difficult to align. The beam width of the antenna is relatively wide at Ku frequencies when compared to the beam width at Ka. Both will actually peak at the same point, but it is more difficult to see a peak at Ku because the beam is broad and the response of the receiver 'flattens' out when you approach maximum signal. Hence the "dithering" alignment technique suggest when aligning on Ku alone.

For those that want to know: the beam width is the 1/2 power points on the antenna pattern. When aligned to a point signal, the antenna is peaked and then adjusted until the received signal drops by 3 db. That point on the response curve is noted and the antenna is adjusted back through the peak until the signal drops 3 db on the other side of peak. The difference between these two points is the beam width in degrees of the antenna.

[dhammis]

Ok, so refresh my memory here please. Which of the birds are Ka and which are Ku? Also, what becomes of the Ku band when SD goes away next year? One last question is about exposed connectors. Should I put a box or something over the exposed connectors (I would assume they are watertight) that are on the outside of my house underneath my eaves? I suppose I could test to see if that was an issue with a garden hose sprayer. When I lived in Detroit I would only have issues with signal during periods of extreme rain and that was very brief. Now the slightest bit of rain or snow will cause the HD to go out while the SD remains. Thankfully where I live there isn't much in the way of snow, but I don't want to hear my wife when we don't get American Idol or something because of the rain. :)

[Supervolcano]

What I'm asking is how did you arrive at that conclusion?
What is that based on?

If the satellite is properly anchored and peaked, snow on the dish (in my experience) affects either signal equally. The width of the signal doesn't matter when the dish is anchored and not moving.

However I could see where atmospheric interference/noise (i.e. rain clouds) would affect the narrower beams more, based on what I've read here on DBSTalk. Thus it's critical peaking those signals as much as possible.
Page 9 of the Slimline Installation Manual.
http://www.solidsignal.com/manuals/Slimline_Dish_Installation_Manual.pdf

Look at the graph.
Ku has a wide upside-down U shape.
Ka has a narrow upside-down U shape.
These U shapes are what's known as the signal strength's curve or slope.

I'm not referring to how wide the "beam's coverage area" is for a region of the country on a particular transponder.

[waynebtx]

So glade i live in South Texas one snow fall in 100 years was two years ago and hope its another 100 before the next one.