St16E internals

[Stephen1988]

Just sharing a few pictures of the internals of a st16E . Hopefully there of some use or interest .
Update 18/11/25 the pictures are a mix of a st16E and a some failed experiment that seems to be a st16s converted into a st16E . The modified controller wasn’t modified by myself so I’m trying to work out what parts are from a true st16E and what belong to a st16s. I’ll update the post shortly to show just st16E . Also it would be nice to know what parts are compatible between both models

 

[DoomMeister]

Here are some files to match that circuit board in the last photos.

According to the documents the OFDM uses 2.4GHz only. The WiFi module shown in the earlier photos uses both 2.4GHz and 5GHz bands.

Do the antenna leads from the WiFi board go to the center mushroom antenna for 5GHz and to an internal antenna for the 2.4GHz?

Do the antenna leads from the OFDM board go to the outer ‘rubber duckie’ omnidirectional stick antennas?

 

[Stephen1988]

Yes the 2 outer antennas go to the ofdm module . The mushroom antenna goes to the WiFi board, there is also an internal antenna that goes to the WiFi board. Is this not similar to the older st16 2 antenna controller that actually had a 3rd antenna inside except in this case this is a 3 antenna controller with a 4th inside, I suppose if u wanted u could mod this one to have the 4th antenna outside also . I didn’t even notice the hidden antenna in this one that was clearly in plain sight until I seen this question

 

[h-elsner]

The hidden antenna is the 2.4GHz WiFi antenna used in pad mode.

 

[Stephen1988]

Another thing that’s might be worth mentioning is if the ofdm module is wired up incorrectly I think it won’t do any difference , the 2 antenna connectors that go to it are indeed from the 2 long antennas each side of the controller and both antennas are the same and use the same length wire to connect to the ofdm board. Why does it even need 2

 

[Stephen1988]

The hidden antenna is the 2.4GHz WiFi antenna used in pad mode.

Is this for updates via OTA. What is the mushroom antenna used for in this case if the video feed is done through the ofdm module, also why does the kit from new come with both a mushroom and a patch antenna, I understand what they both do in a st16s but a bit confused here. If it’s not very apparent yet you probably can see I don’t really know what I’m talking about, it’s all jargon to me , I understand laymans terms

 

[h-elsner]

To have 2.4GHz and 5GHz WiFi band is pretty standard in newer devices (phones, tablets, notebooks..). Newer chipsets support that. Both antenna ports must have an antenna connected. Which band is used depends on SW stack. Legacy Yuneec drones use the 2.4GHz as backup for (old) internet routers that have only 2.4GHz and the 5GHz band for telemetry, videostream, camera settings and Dual Band Control Redundancy. Therefor they have decided to spent a better antenna. The Mushroom antenna is for 360° radiation. Antenna minimum is perpendicular to the antenna. The patch antenna is an alternative to have a more directed antenna beam to have more signal range. The maximum is is perpendicular to the antenna. But you must direct the antenna to the drone.

The SR24 and also the OFDM use two antennas for Antenna Diversity. Simply spoken, the receiver choices the best signal. This is the reason why those antennas should directed 90° to each other to have the effect that one antenna has its maximum where the other has its minimum.

 

[Stephen1988]

so why the patch antenna for the h520e? . I understand for the h520 when u point it directly at the drone but if the e doesn’t use the middle antenna for video feed then would it not make this style of antenna redundant unless u knew exactly where the mast that’s transmitting WiFi came from.