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I'm trying to get a big picture understanding of how video transmission works. How is the video transmitted in FPV transmitters like here?

In the specs, it says FM. So is the analog video (NTSC/PAL) signal frequency modulated with a 5.8 GHz carrier using analog electronics and power amplified to an antenna?

Any reference design, application note, or example circuit would also be helpful. I searched around and couldn't find a good reference.

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In the specs, it says FM.

If you can trust the specs then yes, it transmits both video and audio using FM modulation.

So is the analog video (NTSC/PAL) signal frequency modulated with a 5.8Ghz carrier using analog electronics and power amplified to an antenna?

Probably. The RTC6705 is one IC known to be used in some FPV transmitter modules. It uses a 5.8 GHz VCO (Voltage Controlled Oscillator) and PLL (Phase Locked Loop). It's not completely analog though, as it uses digital counters in the PLL and is programmed via SPI.

You may be able to get more information about a specific device by searching the FCC Equipment Authorization database using the product's FCC ID.

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  • \$\begingroup\$ So modulating the video signal with a 2.5ghz carrier is a possible way to implement this transmitter? I could not find any reference designs or application notes suggesting this idea. So I have no starting point to study these modules and not able to confirm if this idea is correct or not. \$\endgroup\$
    – student_EE
    Commented May 12, 2021 at 17:04
  • \$\begingroup\$ I did some research and found that typically a VCO and PLL is used at the carrier frequency. I have modified my answer to include an example. \$\endgroup\$
    – Bruce Abbott
    Commented May 12, 2021 at 18:51

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