星光灿烂

思想很不错!
投资成本可不低啊!
天线+那么多的高频头+多个复合混合开关
安装也很费事

星光灿烂

蒙城的大概经纬度(官方数据):
纬度latitude ：45.5度
经度longtitude：73.6度(W)

星光灿烂

接收机的差别一般比较大,是烧友必须认真对待的主要器件!
玩家所选的接收机必须支持软件升级,多为: Panset, Fortec, BB or Dreambox那么究竟哪款好?给大家推荐一篇文章参考参考!树立一个概念!

What receiver to buy? Fortec, Panset, BB or Dreambox, etc?
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Want a reliable FTA receiver and do not know what to get? I am not a dealer or affiliated with any manufacturer, so I have no ax to grind. This guide will pass along my observations as a FTA user and give you a good place to start your FTA education.
I have both a Pansat 2500a and a Fortec Ultra and here are the differences. They are both fine and proven receivers with blind search, which are made by the same company, Hyundai. They both can use the others software, but to do that you would need a econd remote to match the flash (add $20 USD). So, If you flash a the ultra with the Pansat, you will need to buy a Pansat remote. And vice versa for Pansat with Ultra flash (same cost for remote).
The Ultra is currently selling for $20-30 USD less than the Pansat. Both are reliable, easy to set up and have s-video and coax TV outputs. Both do not provide electronic program guides for Dish and have limited guides for Bev.The fortec and pansat both have digital audio out.
The Pansat is a bit more deluxe, has some extra features and a two-year warrantee as opposed to a one-year for the Ultra. But, I do not know if that matters, since once you flash either unit, the manufacturers say the warrantee is void.
The Pansat 2500A has a nicer (on screen cosmetics) and little friendlier interface (IMHO not a big deal). If you flash your Ultra to Pansat (I have), it becomes a Pansat in these respects. But a word of caution after the BB clone time bomb and chip fiasco killed so many BB’s, be careful of anti-clone flashes as Black List clams for clones using his Pansat flashes.
However the true Pansat has a motor controller and an optional (costs more) UHF Remote kit, so you can control the same receiver connected to several TVs through walls. You would get the same channel on each TV though. The motor controller enables you to
motorize and automatically position your dish antenna.
With a properly set up system, you would be able to receive any TV or Radio channel automatically on any sat that is visable and receivable in your area on your equipment. That is as long as there are no obstructions, you use the correct LNB, and your dish is large enough.Performance and picture quality are about the same. Both provide an excellent picture to a quality TV The bottom line is:Buy the Pansat if the extra price does not matter and/or you want a proven unit that will allow you to motorize your dish.
Buy the Ultra if you want the best bang-for-the buck in a proven unit and/or do not need a unit that will allow you to motorize your dish.
So what about the PanTec clone that is about $30 USD cheaper than the Fortec Ultra and is said to be a cross between the Pansat and the Fortec? It is said to be able to use both Pansat and Fortec software and even comes with both remotes. It is smaller than either of the better-known units. The downsides are it has just come out, has no history and we do not know what the support will be like or even if it will be truly compatible with all future Pansat and Fortec lashes. Please note: Unlike the Pansat and Fortec units the PanTec is not factory flashed for anything-not even FTA. So it is not ready to do anything out of the box. You will first have to flash it to the PanTec
factory flash (FTA) and then to any other flash. If you flash the PanTec to anything else before you do the factory flash, it will have to be J-Taged or returned to the factory. Also the PanTec loader will
only work with Windows XP it will not work with Win98, Win95 and other OS's.
Buy PanTec ONLY if you are willing to take a chance on an unproven receiver, are prepared to do a more dificult and less-forgiving setup, you have Windows XP and you need the lowest cost. But for even $30-$50 more, I would recommend a Fortec or a Pansat. Since
some dealers are selling the Fortec for less than $10 USD more than they sell the PanTec, there the choice is a no brainer.
What if money is no object? The Dreambox is said to be great! Everything I have heard about it has been positive. Dreambox does provide electronic program guides (EPG) for Dish and Bev and has a built-in hard drive for recording and time-shifting. Its only downside is that since there is a very steep learning curve, I have been told that it may be too dificult for newbies.
The BlackBird is also in that price range but, after the clone-kill timebomb and chip upgrade fiascos, I would never buy a BlackBird. Besides even if BB works, many would argue that the Pansat and Fortec provide equal performance with better support. And you could
buy two (almost three) Fortec Ultras for the price of a single BlackBird.
Another way to go is by using a PCI DVB card in your computer. Its major advantage is that it is easier and faster to recover from an ECM with thie card. Since it is open sourced, you can even fix it yourself, unlike a FTA receiver. The PCI DVB does provide electronic
program guides (EPG) for Dish and Bev and uses your computer's hard drive for recording and time-shifting.But the FTA receiver is much easier to set up than the PCI DVB card. Also the picture quality may not be quite as good with the PCI DVB card as it is with a FTA receiver -- depending on the program and the video card you use with the card.
If you want to buy a card, the Hauppauge Nexus-S (or a clone) is by far the best and easiest to set up and it includes a built-in processor and video outputs. But with a list price of $200 USD, it is also one of the most expensive. IMHO: I own one and it is well worth the premium, if you can afford it. Its TV output with a quality TV and My Theater is high quality. The picture will not be as good with the FREE program ProgDVB.Lots of people swear by the harder-to set up Twinhan card, which will only set you back less than half of the Nexus-S. But, unlike the Nexus-s, it requires a faster computer, installing codecs, and good video card with a TV output if you want to watch on your TV. But with a steet price of $70-$80 USD, many people find that it is the lowest priced reliable ticket to FTA.
This is not meant to teach you everything you need to know. However, it will provide a good foundation for your FTA education.


希望对你有所帮助!

星光灿烂

仰角是指接收站天线仰望卫星的视线与水平面构成的夹角。而方位角是指在接收点水平面上作一条接收站仰望卫星的视线的正投影线，从接收点的正北方开始，顺时针（即北──东──南──西）方向转到这条正投影线的角度。
明白了仰角和方位角的概念后，我们可以按下面两个公式将其计算出来：
(实际上是按球坐标换算而来)



式中:
AZ为方位角；
EL 为仰角；
& 为卫星定点经度；
Q为地面站经度；
B 为地面站纬度；
R 为地球半径，6378.1公里；
H 为卫星距地面的垂直高度，35786.5公里(这是均方根值,同步轨道有一个带宽,不同的卫星定位在不同的轨道位置,故该值是不同的,但对一般的调星计算可以使用此值)。
注意：按以上公式计算所得为正馈天线（即中心聚焦天线）的仰角，如为偏馈天线，其仰角为：E－天线的偏馈角。(一般偏馈天线上的仰角刻度即是这里的计算值,在加工刻度时已经考虑了偏馈角的影响)

按上述公式计算时尚未考虑磁偏角的影响。磁偏度是地球磁场南极向西偏离地球地理北极产生的，当用地磁北极定向时，须将地理南极定向的角度AE加上地磁偏度。在地球上的不同位置看地磁偏角是不一样的,蒙城的地磁偏角约为15度左右.

网上有许多计算仰角和方位角的软件,值得注意的是,有的软件没有考虑地磁偏角,有的已经考虑了地磁偏角,使用时要先看仔细了!

星光灿烂

使用公式计算天线的仰角和方位角是比较麻烦，怕麻烦可以在网上直接计算，给大家一个链接，内有场强分布图，角度计算，安装指导：http://www.kusat.com/go.php?path=/install/locate.php

内部预植了北美上空最主要的卫星轨道位置，和加拿大大部分地区的经纬度，你只要简单的选择就可以获得角度值。注意所得角度值没有考虑地磁偏角！