qca 指定频道扫描_如何扫描（或重新扫描）电视上的频道

qca 指定频道扫描

So, you’re trying to watch free over-the-air TV, but you can’t find any channels. That’s perfectly normal. You just need to run a quick channel scan (or rescan), and you’ll be good to go.

因此，您正在尝试观看免费的无线电视，但找不到任何频道。完全正常。您只需要运行快速频道扫描(或重新扫描)，就可以了。

为什么我必须扫描频道？ (Why Do I Have to Scan for Channels?)

Digital television (ATSC 1.0) has served as the standard for free, broadcast TV since the ’90s. And like any 20-year-old technology, it’s a little quirky. You’d expect a TV to know which local stations are available, like a radio, but that isn’t the case. Instead, your TV keeps a list of which stations are available. Weird, huh?

自90年代以来，数字电视(ATSC 1.0)一直是免费广播电视的标准。与任何具有20年历史的技术一样，这有点古怪。您可能希望电视能知道哪些本地电台可用，例如收音机，但事实并非如此。相反，您的电视会保留可用电台的列表。奇怪吧？

Do you know how old TVs (and radios) had to be tuned to stations by hand? Well, when you scan for channels on a TV, it’s basically performing that process for you. The TV slowly runs through every possible television frequency, making a list of each available channel along the way. Then, when you go to watch TV later, you’re just flipping through that list. Naturally, that list needs to be updated every once and a while, and you have to start the scanning process all over again.

您知道必须手动将多台旧电视(和收音机)调到电视台吗？好吧，当您在电视上扫描频道时，基本上就是为您执行该过程。电视缓慢运行于每个可能的电视频率，并列出了沿途每个可用频道的列表。然后，当您以后去看电视时，您只是在浏览该列表。自然，该列表需要不时更新，因此您必须重新开始扫描过程。

我什么时候应该扫描频道？ (When Should I Scan for Channels?)

You need to scan for channels every time there’s a change in local broadcast frequencies. That means you have to rescan every time you move, every time you buy a new TV or antenna, and every time a local TV station changes to a different broadcast frequency.

每当本地广播频率发生变化时，您都需要扫描频道。这意味着您每次移动时，每次购买新电视或天线时以及本地电视台更改为不同的广播频率时都必须重新扫描。

In this past, this roughly translated to “if the TV ain’t working, scan for channels.” But right now, America is undergoing a broadcast TV transition. Due to an FCC mandate, broadcasters are steadily switching over to 4K-ready, ATSC 3.0 compatible frequencies that don’t interfere with cellular frequencies. As a result, all TVs are going to lose track of local channels slowly. Plus, entirely new channels could pop up in your area, and your TV won’t know that they’re there.

在过去，这大致翻译为“如果电视无法正常工作，请搜索频道”。但是现在，美国正在经历广播电视的过渡。由于FCC的要求，广播公司正在稳定地切换到不干扰蜂窝频率的4K就绪，ATSC 3.0兼容频率。结果，所有电视将逐渐失去对本地频道的跟踪。另外，全新的频道可能会在您所在的地区弹出，而您的电视也不知道它们在那里。

The solution? Scan for new channels every month, or every time you notice that a local broadcast goes missing. It’s an easy process, and it’s worth doing for the sake of free OTA TV.

解决方案？每月或每当您发现本地广播丢失时扫描新频道。这是一个简单的过程，因此值得免费使用OTA电视。

如何扫描(或重新扫描)频道 (How to Scan (or Rescan) For Channels)

Scanning (or rescanning) for channels is mostly an automated process. All you have to do set that process in motion through a few simple steps. And while these steps are different for each TV, the process is pretty similar on every TV out there.

扫描(或重新扫描)频道主要是一个自动化过程。您所要做的只是通过几个简单的步骤就可以启动该过程。尽管每个电视的这些步骤都不同，但每个电视上的过程却非常相似。

Make sure your TV is connected to an antenna.

确保您的电视已连接至天线。
Press the “Menu” button on your remote control. If you don’t have a remote, your TV should have a built-in “Menu” button.按下遥控器上的“菜单”按钮。如果没有遥控器，则电视应具有内置的“菜单”按钮。
Find and select the “Channel Scan” option in your TV’s menu. This option is sometimes labeled “Rescan,” “Tune,” or “Auto-tune.”在电视菜单中找到并选择“频道扫描”选项。有时将此选项标记为“重新扫描”，“调整”或“自动调整”。
If you can’t find the “Channel Scan” option, dig through the TV’s “Settings,” “Tools,” “Channels,” or “Options” menu. On some TVs, you have to press the “Input” button and go to “Antenna.”如果找不到“频道扫描”选项，请浏览电视的“设置”，“工具”，“频道”或“选项”菜单。在某些电视上，您必须按“输入”按钮并转到“天线”。
Once your TV starts scanning for channels, find something to do. Channel scanning can take upwards of 10 minutes.电视开始扫描频道后，请找点事做。频道扫描最多可能需要10分钟。
When scanning is complete, your TV will either display how many channels are available or drop you back into a broadcast.扫描完成后，电视将显示可用的频道数量或将您带回广播。
Still missing some channels? Try running another scan, or use Mohu’s website to double-check what channels are available in your area. You may need to move your antenna for better reception, too.

仍然缺少一些频道？尝试进行另一次扫描，或使用Mohu的网站仔细检查您所在地区可用的频道。您可能还需要移动天线以获得更好的接收效果。

If you’re having trouble finding the “Channel Scan” option on your TV, then it’s time to consult the manual. You can usually find a manual by searching the web for the TV’s make and model along with the word “manual.”

如果您在电视上找不到“频道扫描”选项时遇到问题，那么该参考手册了。通常，您可以通过在网络上搜索电视的品牌和型号以及“ manual”一词来找到手册。

为什么我的电视无法自动扫描频道？ (Why Can’t My TV Automatically Scan for Channels?)

Admittedly, this is a clunky, somewhat annoying process. If radios don’t need to perform tedious rescans, then why can’t TVs automatically scan for channels?

诚然，这是一个笨拙的过程，有些令人讨厌。如果收音机不需要执行繁琐的重新扫描，那么电视为什么不能自动扫描频道？

Well, they do—kind of. Scanning (or rescanning) is an automated process; you’re just forcing your TV to enter that process. The reason why your TV doesn’t automatically scan for new channels without your permission is that, well, that would be obnoxious and interfere with your TV watching.

好吧，他们确实如此。扫描(或重新扫描)是一个自动过程。您只是在强迫电视进入该过程。电视未经您的允许不会自动扫描新频道的原因是，这很令人讨厌并且会干扰您的电视观看。

Remember, we’re dealing with 20-year-old technology. There’s nothing wrong with it; it’s just got a few quirks. One of those quirks is that, while a TV is scanning, it can’t be used to watch television. If your TV routinely scanned for new channels without your permission, you’d have to deal with random 10-minute bouts of silence every once and awhile. It could even happen while you’re watching an important soap opera or football game.

请记住，我们正在使用已有20年历史的技术。这没什么不对的。只是有一些怪癖。这些怪癖之一是，尽管电视正在扫描，但不能用来观看电视。如果您的电视在未经您许可的情况下例行扫描新频道，则您将不得不不时地随机处理10分钟的沉默。当您观看重要的肥皂剧或足球比赛时，甚至可能会发生这种情况。

If you’re wondering why your radio doesn’t need to perform automatic scans, that’s because it’s easy to tune a radio on the fly. A good radio signal is filled with a mix of loud and quiet parts (music), while a bad signal is filled with monotonous static or silence. So, most radios have a built-in tuning circuit that simply checks the amplitude response of radio frequencies. When you press “next” on your radio, it just runs some frequencies through the tuning circuit and locks in on whatever has a mix of loud and quiet parts.

如果您想知道为什么无线电不需要执行自动扫描，那是因为可以很容易地即时调整无线电。一个好的无线电信号充满了响亮而安静的部分(音乐)，而一个坏的信号充满了单调的静态或静默。因此，大多数无线电设备都具有内置的调谐电路，可以简单地检查无线电频率的幅度响应。当您在收音机上按“ next”时，它只是通过调谐电路运行一些频率，并锁定包含高声和低声部分的任何东西。

别担心频道扫描很快就会消失 (Don’t Worry; Channel Scanning Will Go Away Soon)

As we mentioned earlier, the FCC is transitioning to the ATSC 3.0 broadcast standard. It’s a fascinating change that’s worth looking into. In the next decade, ATSC 3.0 will allow us to watch broadcast TV in 4K on practically any device, including phones, tablets, and cars.

正如我们前面提到的，FCC正在过渡到ATSC 3.0广播标准。这是一个令人着迷的变化，值得研究。在接下来的十年中，ATSC 3.0将使我们能够在几乎任何设备(包括电话，平板电脑和汽车)上观看4K广播电视。

Naturally, channel scanning would be a pain on a handheld device or in a car. As you move around town (or even around your house) frequencies will shift in quality and availability. So, the FCC will eliminate the need for channel scanning in ATSC 3.0. Eventually, you’ll forget that you ever had to sit for 10 minutes in front of your TV while it scans for channels, and this guide will disappear into the ether.

自然，在手持设备或汽车上进行频道扫描会很麻烦。当您在城镇(甚至房屋)周围移动时，频率会改变质量和可用性。因此，FCC将消除在ATSC 3.0中进行通道扫描的需要。最终，您会忘记在扫描频道时曾经不得不坐在电视前10分钟，而该指南将消失在以太中。

翻译自: https://www.howtogeek.com/424853/how-to-scan-or-rescan-for-channels-on-your-tv/

qca 指定频道扫描