SatelliteGuys MPEG4 Contest!
- Thread starter Scott Greczkowski
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Looks like no matter how much proof you get the guys at the tivocommunity forum don't believe it
http://www.tivocommunity.com/tivo-vb/showthread.php?t=267820
http://www.tivocommunity.com/tivo-vb/showthread.php?t=267820
BFG said:It looks like only 1 set of local channel numbers? I guess they only map dwon the HD channels and not the SD locals since it's an HD box?
Interesting anyways and banners and epg look purty
That made sense to me initially, and then I got to thinking about the problem we experienced with the 2004 Olympics when NBC broadcast "live" coverage on their SD channel and old events on their HD feed. I recall they mentioned something about a remedy to that issue for 2006...let's hope so if those of us in the Top 12 may have only one feed by then.
minorthr said:
Whats funny is they dont even believe their own fearless leader Ken who saw it with his own eyes and reported it.
I guess it just goes to show that no one believes Ken anymore.
Scott Greczkowski said:Whats funny is they dont even believe their own fearless leader Ken who saw it with his own eyes and reported it.
I guess it just goes to show that no one believes Ken anymore.
Is there some sort of history here? Seems like you slam this fella every chance you get...
Just asking as I am new here...
charper1 said:
You are correct. It is called "realized or apparent gain". The staadard militray fixed station dish is about 30 ft in diameter. that dish alone provids 30dB of "apparent gain" at the feed horn. This is with 100db of attenuation from the geosychronous bird. Having said that, there are other parameters as well. I don't think these litte DBS dishes use waveguide, (fixed or flexible) so we don't have to worry about the 'cut', but the new dish is not even in its rate of curvature nor is ot round. That is to say, if we plotted signals coming from different parts of that dish, we would find dramitic (say up to 9db off the top of my head) differences in apparent gain as meausured at the feed. Those readings may be the norm of the future, but I suspect (& hope) that it was just inexperience in dialing that new monster in.
What the heck did you just say?? There is no 30ft “staadard militray fixed station dish antennas”, the sizes are all over the place depending on the band and use.lovswr said:
At what frequency does it provide “30db of apparent gain”? At C band receive, a 30ft antenna would provide about 49-50dbi gain and at Ku maybe 59dbi gain. What is the “100db of attenuation from the geosychronous bird”? Do you mean the 205db or so space loss at DBS downlink frequencies? What is the “cut” we don’t have to worry about with waveguide? What does the rest of this post mean?????
Bob (confused)
The OE-222 Parabloic antenna, used by the AN/FSC-52 & the AN/FSC-78/39 (in the 39 configuration...the 79 means that you got the big dish which is not quite 100 feet in diameter) are standard DSCS dishes. This is fixed station. Places like Landstuhl, k-16, ECTC, Ft Meade, ROC, LOC, Sunnyvale, Ft. Belvoir & of course the school at Ft. Gordon. You may be referrering/used to the little tactical vans like the 85/93 (army) 86/100 (air force) which use the the quick setup/tear down dishes or heck even MILSTAR.
All of the fixed stations above use non flexible wave guide. They are literally "cut" (actually if you run your hand along the inside it just feels like smooth waves to your fingers) so that they attenuate certain, unwanted fequencies & let the ones that you want ( 7.9Ghz to 8.4Ghz up & 7.2GHz to 7.5GHz down) pass through with the least amount of attenuation.
Yes I'm talking about the approx. 200dB of attenuation for a ground station, bird, ground station trip.
Bob, the gain of a parabolic antenna is not constant over it's entire surface, even at the same frequency. At any certain point, if you could isolate your signal, you will find that as you move away from that point in any direction, your gain will change.
All of the fixed stations above use non flexible wave guide. They are literally "cut" (actually if you run your hand along the inside it just feels like smooth waves to your fingers) so that they attenuate certain, unwanted fequencies & let the ones that you want ( 7.9Ghz to 8.4Ghz up & 7.2GHz to 7.5GHz down) pass through with the least amount of attenuation.
Yes I'm talking about the approx. 200dB of attenuation for a ground station, bird, ground station trip.
Bob, the gain of a parabolic antenna is not constant over it's entire surface, even at the same frequency. At any certain point, if you could isolate your signal, you will find that as you move away from that point in any direction, your gain will change.
my question is.. what in the world does OE-222 have anything to do with the DirecTV A9 dish, or anything at all in this thread?
my thoughts for the signal loss is because the Ku LNBs are not in the focal point of the dish.. The Ka and 101 Ku LNBs are dead center, while the 110 and 119 lnbs are on the wing.
my thoughts for the signal loss is because the Ku LNBs are not in the focal point of the dish.. The Ka and 101 Ku LNBs are dead center, while the 110 and 119 lnbs are on the wing.
I took the training class on the h20 and this dish today. #1 the multiswitch used in the first configuration was not needed by any means, it uses a built in switch just like the triplsat does. #2 the 110 and 119 lnb's are connected to the 99,101,103 lnb via a small two wire jumper the size of a phone wire. #3 The signal is low due to a b-band converter(which I still have no idea what is) that is put inline just b4 the receiver. If you put a regular receiver on this system you will get the same signal as always, but there is so much going on with the power consumption that the signal readings read lower. It is a pain to peak. Atleast at first try. I am sure it will get easier with time. A pole mount is required to have 2 feet of pole in the ground and 150lbs on concrete. Sorry to ramble but there was so much info that I have a hard time remembering it, in a specific order. If there are any specific question I will be glad to answer them if I can. And yes we were told that right out of the box you must do a forced software upgrade for the unit to perform correctly. In two weeks the Nashville and Bhm dma's will begin to use this dish on HD and triple sat upgrades. I will post MY first install as soon as it happens.
When you say “ the gain of a parabolic antenna is not constant over it's entire surface”, if you mean the feed usually under illuminates the reflector at the outer edges of the dish on most designs, I will agree (trying to be nice) as this helps reduce spillover on a prime focus antenna. Otherwise the “gain” of any given “section” of a parabolic reflector will be the same for any other “section” if they have the same surface area and you are measuring at the reflector focal point.lovswr said:
At DBS Ku downlink freqs there is about 205dB space loss from the satellite to the antenna on your roof. That is one way, not 200dB round trip. At 7.5GHz DSCS downlink freqs there is about 201dB loss one way from the satellite to the ground station.
Bob
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