穿越机：图传表中的 Factory 开关起什么作用？

Factory开关决定了Betaflight 与图传的通讯方式，简单来说：

FACTORY 开关打开，那就是用图传硬件内部自带的图传表工作。比如A1，应该是5866MHz，但是如果你不小心在图传表中将A1输入成了5860MHz，则图传继续会用硬件自带的5865MHz，而不是你指定的5860MHz。这样对硬件工作比较友好。夸张点说，哪怕你给图传参数表的频率都设置为0，那图传也会正常工作。但是在OSD中，还是会显示你人为设置的图传频率值，比如5860MHz或者0MHz。

FACTORY 开关改为 CUSTOM ，则意味着使用自定义频率，按照上例，图传在A1就以5860MHz工作，而非工厂给定的5860MHz工作。你甚至可以指定一般图传表中不存在的频率来工作。对于一些没有内置图传表的图传，只能以这种方式工作，比如 IRC Tramp 协议，就必须关闭FACTORY 开关，并指定一个频率来工作。

以下是 SmartAudio 协议下的常见图传表

以下是 IRC Tramp 协议下的常见图传表

下文是图传表的详细解释，来自BetaFlight的WiKi解说：https://github.com/betaflight/betaflight/blob/master/docs/VTX.md

VTX Table

As of Betaflight 4.1.0, band/channel and power level information needed to control videotransmitters is no longer hardcoded, but stored in a new facility called vtxTable.

The contents of the vtxTable need to be setup manually. They need to match the hardware, local laws and regulations, as well as user preferences.

The contents of the table can be examined by typing the command vtxtable into the cli. Example:

# vtxtable vtxtable bands 5 vtxtable channels 8 vtxtable band 1 BOSCAM_A A FACTORY 0 5845 5825 5805 5785 5765 5745 0 vtxtable band 2 BOSCAM_B B FACTORY 0 5752 5771 5790 5809 5828 5847 0 vtxtable band 3 BOSCAM_E E FACTORY 0 0 0 0 0 0 0 0 vtxtable band 4 MYBAND M CUSTOM 5745 5769 0 5806 0 5843 0 0 vtxtable band 5 RACEBAND R FACTORY 0 0 0 5769 5806 5843 0 0 vtxtable powerlevels 3 vtxtable powervalues 14 20 26 vtxtable powerlabels 25 100 400

1 2 3 4 5 6 7 8 9 10 11 12

# vtxtable vtxtable bands 5 vtxtable channels 8 vtxtable band 1 BOSCAM_A A FACTORY    0 5845 5825 5805 5785 5765 5745    0 vtxtable band 2 BOSCAM_B B FACTORY    0 5752 5771 5790 5809 5828 5847    0 vtxtable band 3 BOSCAM_E E FACTORY    0    0    0    0    0    0    0    0 vtxtable band 4 MYBAND   M CUSTOM  5745 5769    0 5806    0 5843    0    0 vtxtable band 5 RACEBAND R FACTORY    0    0    0 5769 5806 5843    0    0 vtxtable powerlevels 3 vtxtable powervalues  14 20 26 vtxtable powerlabels 25 100 400

Bands and channels

The example above contains 5 bands, each with a name, a single-letter abbreviation, a factory flag and eight frequencies.

The factory flag controls how Betaflight communicates with the vtx.

When the flag is set to FACTORY, Betaflight sends the vtx a band and channel number. The vtx will then use its built-in frequency table. In this mode, the actual contents of the vtxtable are not send the vtx. They are only used for display in the OSD and similar places. As such, bands with the flag set to FACTORY should be set to match the built-in frequency table of the vtx.

When the flag is set to CUSTOM, Betaflight sends the vtx the frequency it should use. This mode utilizes the contents of the table and allows the user to create custom bands with whatever frequencies they like. Videotransmitters without a built-in table, such as IRC Tramp or rtc6705 only support CUSTOM.

Entries of the vtxtable can be blocked by setting their frequency to 0. This is especially useful for bands set to FACTORY: The spots of unwanted entries of the videotransmitter’s built-in table can be set to 0, effectively disabling them. In the example above this was used to only allow frequencies between 5725 and 5875 MHz, as a German pilot would want it to comply with German laws. Additionally, the Fatshark band was replaced with a new custom one.

As a starting point, the following table contains the commonly used frequencies:

# This table should not be used as-is, but trimmed down according to local laws and regulations. vtxtable band 1 BOSCAM_A A FACTORY 5865 5845 5825 5805 5785 5765 5745 5725 vtxtable band 2 BOSCAM_B B FACTORY 5733 5752 5771 5790 5809 5828 5847 5866 vtxtable band 3 BOSCAM_E E FACTORY 5705 5685 5665 5645 5885 5905 5925 5945 vtxtable band 4 FATSHARK F FACTORY 5740 5760 5780 5800 5820 5840 5860 5880 vtxtable band 5 RACEBAND R FACTORY 5658 5695 5732 5769 5806 5843 5880 5917

1 2 3 4 5 6 7

# This table should not be used as-is, but trimmed down according to local laws and regulations. vtxtable band 1 BOSCAM_A A FACTORY 5865 5845 5825 5805 5785 5765 5745 5725 vtxtable band 2 BOSCAM_B B FACTORY 5733 5752 5771 5790 5809 5828 5847 5866 vtxtable band 3 BOSCAM_E E FACTORY 5705 5685 5665 5645 5885 5905 5925 5945 vtxtable band 4 FATSHARK F FACTORY 5740 5760 5780 5800 5820 5840 5860 5880 vtxtable band 5 RACEBAND R FACTORY 5658 5695 5732 5769 5806 5843 5880 5917

Power levels

In addition the the frequency, videotransmitters also need to know how much power they should use for transmission. The example shown previously contains three power levels, each with a value and a label. The label is shown to the user in the OSD, while the value is sent to the vtx.

Power levels should be setup to match the hardware in use.

IRC Tramp devices should use:

vtxtable powerlevels 5 vtxtable powervalues 25 100 200 400 600 vtxtable powerlabels 25 100 200 400 600

1 2 3 4

vtxtable powerlevels 5 vtxtable powervalues 25 100 200 400 600 vtxtable powerlabels 25 100 200 400 600

rtc6705 should use:

vtxtable powerlevels 2 vtxtable powervalues 1 2 vtxtable powerlabels MIN MAX

1 2 3 4

vtxtable powerlevels 2 vtxtable powervalues 1 2 vtxtable powerlabels MIN MAX

Please note that turning off rtc6705 devices is not possible using powervalues. Use pitmode instead.

SmartAudio V1.0 devices should use:

vtxtable powerlevels 4 vtxtable powervalues 7 16 25 40 vtxtable powerlabels 25 200 500 800

1 2 3 4

vtxtable powerlevels 4 vtxtable powervalues 7 16 25 40 vtxtable powerlabels 25 200 500 800

SmartAudio V2.0 devices should use:

vtxtable powerlevels 4 vtxtable powervalues 0 1 2 3 vtxtable powerlabels 25 200 500 800

1 2 3 4

vtxtable powerlevels 4 vtxtable powervalues 0 1 2 3 vtxtable powerlabels 25 200 500 800

SmartAudio V2.1 devices vary depending on their model. Check the manufacturers website.

For these devices the powervalues are the output power in dBm.

To query the available power levels from a SmartAudio 2.1 VTX enter the vtx_info command with no parameters. This will report the available power settings thus: