Typhoon H480 "older model" antenna question

[SkyVidTek]

I purchased a used H480 as a backup and recently had the covers off for an inspection. This was one of the earlier H models before the internal antennas were extended out parallel to the landing gear legs. This one seems to have had a partial upgrade with the newer plastic antenna stubs added and the antenna wires routed out through the stubs. I noticed that the metallic tubular pieces which are on the later antennas internally, were not present on this update.
So, what is the purpose of the tubular metal pieces normally on the antennas, but missing on these? Does it have to do with the tuning length? I have flown it without any reception problems albeit only out about 250-300m.

 

[Steve Carr]

Does it have to do with the tuning length?

Yes. The exposed center conductor is the part that receives and transmits. It's length is set for the frequency (2.4GHz) for the telemetry and control signals. The video antenna is in the camera.

 

[h-elsner]

The metallic tubular pieces are still present in the newer models. They are inside and the center wire of the coax cable is longer (5/8 lambda). The brass tube is made to tune the antenna for this. It is called balun. The construction is called a Baily antenna or of skirt feed antenna.

https://www.w8ji.com/Image1/Skirt_feed.jpg

The older antennas are shortened lambda/4 antennas also tuned by a balon.

Look inside one of the two SR24 antennas:

The center wire of the coax cable goes through and the copper shield is connected on the top of the tube.

br HE

 

[SkyVidTek]

The metallic tubular pieces are still present in the newer models. They are inside and the center wire of the coax cable is longer (5/8 lambda). The brass tube is made to tune the antenna for this. It is called balun. The construction is called a Baily antenna or of skirt feed antenna.

https://www.w8ji.com/Image1/Skirt_feed.jpg

The older antennas are shortened lambda/4 antennas also tuned by a balon.

Look inside one of the two SR24 antennas:
View attachment 19449
The center wire of the coax cable goes through and the copper shield is connected on the top of the tube.

br HE

Thanks for the explanations gentlemen. So with the "baluns" missing on my aircraft antennas, I assume it would reduce the range and or quality of the reception of the 2.4ghz control and telemetry signals.

I should look for replacement antennas from a parted out (crashed) later model H480 aircraft, as I do not know the P/N and have never seen these on any website as a Yuneec replacement part.

 

[Mrgs1]

Thanks for the explanations gentlemen. So with the "baluns" missing on my aircraft antennas, I assume it would reduce the range and or quality of the reception of the 2.4ghz control and telemetry signals.

I should look for replacement antennas from a parted out (crashed) later model H480 aircraft, as I do not know the P/N and have never seen these on any website as a Yuneec replacement part.

Typhoon H/H-Pro Parts List

Typhoon H/H-Pro Parts List Let me know if I made any Mistakes or you have more to add...:)

yuneecpilots.com

Have a look in here for part number.

 

[SkyVidTek]

I see you have a p/n for the complete board with antennas.... YUNTYH135SVC , Didn't see just the antenna separately.

I assume that the antennas are not available separately, from Yuneec, so if I bought the board complete at least I would have a spare board....

BTW, I had downloaded your list previously and found it useful.... is it possible to produce it in a more simple readable font like Arial? I find that heavy font hard to read.....