Skyreat yagi antenna for DJI drones

[Firekite]

I happened across this aftermarket “yagi” antenna accessory while looking at various things for my DJI Mini 2 drone. I was immediately suspicious of its claims and even its fundamental design. I’m almost considering buying one just to physically dissect it. The elements do not appear arranged in a way that would be effective even if there’s actually something embedded in all that plastic between the little pieces of aluminum. It seems like they just stuck some pieces of aluminum round stock like rungs in a ladder in some plastic (that will inevitably break off in your bag).

Additionally, the entire point of a yagi isn’t to amplify the signal but to change the radiation pattern to focus what power there is in a very specific direction. But of course their marketing illustrations all seem to have the drone somewhere off to the side.

Anyway, am I crazy? Or is this $1.50 worth of snake oil in a $15 box?

Skyreat Antenna Range Extender Yagi-UDA 5.8Ghz Signal Boosters for DJI Mini 2 / DJI Air 2S / Mavic Air 2 Drone Specific Accessories https://smile.amazon.com/dp/B08HHZS166

 

[slicerwizard]

What exactly do you think should be embedded in the plastic? What do you expect to find when dissecting it?

 

[Firekite]

What exactly do you think should be embedded in the plastic? What do you expect to find when dissecting it?

Why exactly do you ask?

 

[slicerwizard]

You wrote " It seems like they just stuck some pieces of aluminum round stock like rungs in a ladder in some plastic". You don't seem to think that describes a Yagi.

 

[Firekite]

You wrote " It seems like they just stuck some pieces of aluminum round stock like rungs in a ladder in some plastic". You don't seem to think that describes a Yagi.

And you do? I’m asking here for clarification because I’m not an expert in these matters, but my understanding is that a yagi has resonant antenna elements, connected to each other, not just a sort of wave guide hoping to contain signals between pieces of metal spaced smaller than the wavelength (in this case 2.4GHz or 5.8GHz).

It’s hard to tell from text maybe, but it sounds like you’re challenging without providing any information rather than asking questions to learn.

 

[AK9R]

...a yagi has resonant antenna elements, connected to each other...

Quoting from Wikipedia: "Yagi–Uda antennas consist of a single driven element connected to a radio transmitter and/or receiver through a transmission line, and additional 'parasitic elements' with no electrical connection, usually including one so-called reflector and any number of directors."

Note that the reflectors and directors are parasitic. They are not electrically connected to the director.

Also, note that the reflectors and directors are not resonant on the antenna's tuned frequency. The reflector is typically longer than the resonant driven element and the director(s) are typically shorter than the resonant driven element.

You may be thinking of a log-periodic dipole array. In an LPDA, the elements are connected to each other. But, that's not a Yagi.

 

[slicerwizard]

And you do?

Yes, I do think that describes a Yagi.

I’m asking here for clarification because I’m not an expert in these matters, but my understanding is that a yagi has resonant antenna elements, connected to each other, not just a sort of wave guide hoping to contain signals between pieces of metal spaced smaller than the wavelength (in this case 2.4GHz or 5.8GHz).

It’s hard to tell from text maybe, but it sounds like you’re challenging without providing any information rather than asking questions to learn.

I guess my question asking skills aren't the best. I didn't assume what you knew or didn't know and rather than formulate a reply based on assumptions, I asked for clarification.

 

[Firekite]

Note that the reflectors and directors are parasitic. They are not electrically connected to the director.

You’re right, I was getting it wrong.

You may be thinking of a log-periodic dipole array. In an LPDA, the elements are connected to each other. But, that's not a Yagi.

Whoops. Yes, I was turned around on that.

I guess my question asking skills aren't the best. I didn't assume what you knew or didn't know and rather than formulate a reply based on assumptions, I asked for clarification.

Because you didn’t actually answer the question I asked, and because of the wording of the questions you asked in response, it came across (to me) as a condescending challenge, or at best a poorly executed Socratic response. I had laid out my (mistaken) expectations in the original post.