Questions Re: DirecTv Transponder Signals

nomad297 wrote:
When I setup my dish I always use the built-in signal strength meter with my receivers. The screen always defaults to satellite 101 and Transponder 1. I always use this default setting to zero-in my dish. The maximum signal I have ever obtained on that transponder is 98%. If I switch-over to the screen showing all of the different transponders I will see several with 100% and several with much lower numbers, and even a couple zeros.

My questions are, if I have 100% on one transponder, why don't I have 100% on all transponders? Aren't they all coming from the same place and going to the same place? Also, why will my other receivers show different signal strengths? They're all hooked up to the same dish pointing to the same place. And, why is it that sometimes when I have a clear sky with no obstructions in different locations, I can't get as high of a signal on 101, Transponder 1?

I never have a problem with any channels if I can get 101, Transponder 1 above 70% (maybe lower, but that's the lowest I have ever had to settle on), so my questions aren't something I have to get answers for. I am just curious as to why things are the way they are.

Bruce

I have no idea. However, I set up my portable directv dish (18 ich) I use transponder number 5. You could use any transponder, but I have always used 5 as I know what is a good signal on 5. If it is good on 5, then it is good on all.

I have set up lots of C band dishes, which go from low in the west, to near the horizon in the east. Now there is where the skew is very critical for the far ends in the east and west, not to mention level, and center lock down point in the south.

I thought skew would make more difference than it did which is why I played with skew after setting up. I was just surprised that so little difference was noted. I was wondering if my latitude during this test, Florida Gulf Coast, would make skew less important than in more northern latitudes.

Also, SWM does not need or care about skew. You can use SWM with a single LNB. It's the specific LNB/antenna combo that requires or does not require skew.

Moving the dish 20+ degrees either way would not effect 101 but it "should" have a dramatic effect on 99 and 103.

I guess I didn't make my post clear. After getting my dish set on 101 I switched to 99 and then 103 and played with the skew. As I stated above, it made little difference by changing it +/- 20 degrees. I do have HD and have a slimline dish.

gatorcq wrote:
But is sounds as if you have only SD (101).

Who are you referring to?

Bruce

101, does not need skew.
Now if you have SWM, or the earlier 3 LNB (99,101, 103), yes skew does matter.
But is sounds as if you have only SD (101).

What is a transponder.. It is a combination Receiver/transmitter which responds to commands. What you have on the Satellite is not really a transponder (it is a repeater) but if that is what they want to call it.. I wont stop them.. In any case the key is the "Transmitter"

I am, currently, sitting between several transmitters
One is a 35 watt VHH/UHF ham radio transmitter
2 5 watt (DC input to the final) CB's and one is a 100 watt Multi-band Ham rig, there are some others lying about as well.

Clearly if you are at a distance and I set the little hand held VHF radio on 1 watt and transmit and you pick it up. say it moes your needle 25 percent of the way.

Then I go into the other room and key the 100 watt on the same frequency.. The pin bends around the stop as it were.

Some of the transponders have a bit more power on the transmitter than others. or rather effective power.. Why is this: FOotprints for one.

You have some transponders that are CONUS beams (COntinental United States)

Some are Spot beamed.. Clearly to cover the entire country takes more power than to cover, say.. Kentucky (Picked state at random) if they are a bit off on teh calc you might get a stronger signal on one or the other beam.

And the difference between 98 and 100... Is basically "Forget it".

Now if it was 60 and 90, that would be different, but 2 points is nothing.

Oh, one other factor.. You said 1 is often the lower one and others (Let me guess around 10-12) are higher..... 1 is the "Band edge" as far as the antenna is designed.. 10-15. Middle of the window.

I understand what skew does Bill, but I appreciate your info. I was just playing around with it to see how critical it really was and on the Florida Gulf Coast it didn't make much difference. By my post I was wondering if my latitude made it less critical than further north and that seems to be the case from another post. All I do know for sure it I like sat TV, set up my dish quickly, and wouldn't be without it.