Hoverfly HF Sport and UHF noise

[Aerovideo]

I just discovered this last night as I was running the frequency tester off my EZuhf Rx. The biggest culprit was my power switching regulator (TBS CORE) but I think I can fix that a little bit with a grounded tin shield (just learned about it . The next surprise was when I powered up the ole HFSport, doah! It wasn't nearly as bad as the TBS Core but it did raise the noise floor. Not sure what to do about that if anything as I've been flying fine with the sport board and ezuhf on several different quads without problems for quite a while. However my latest quad, and Aquacopter, has very little space so the EZuhf Rx sits right above the sport board. This definitely won't be a long range quad as the VTx is inside the enclosure too.

Just curious if anyone else had noticed this with the Sport or Pro boards and if they've done anything about it?

Paul

 

[workshop]

Paul,

I am dealing with the same issues with my waterproof quad. What is your noise floor with everything off and with everything on (except EzUHF TX of course). Even with a noise floor of about -70db (way high), I am still able to go a mile on standard power.

On my long distance gear, I try to get the noise floor below -90 which is not hard with the right gear and mitigation techniques. What VidTX are you using? I have found that many VidTXs step all over the 433MHz band with the 1.3GHz gear being the worst offender all other things remaining the same.

Jeff

 

[Aerovideo]

Hey Jeff,

With just the EZUHF Rx on my noise floor is around -100db although there's a spike at 432MHz. When I power up the sport board it goes up to about -95db and when I power up the TBS core which in turn powers up the camera and ImmersionRC 5.8Ghz Vtx then it jumps to -85db to -90db but with more spikes. I hope I'm referring to all this correctly as I'm a newbie at radio frequency analysis

I recently switched from 1.3GHz video to 5.8GHz video, the antennas are so much easier to deal with.

It's interesting, the VTx by itself doesn't seem to do much as does the TBS core by itself. It's not until I plug something into the core that the floor goes up. When something gets plugged in that must fire up the power regulators. But as soon as I fire up the HFSport the floor does go up a little.

So it looks like I'm probably okay then if you've been out a mile with a -70db noise floor. I don't usually fly too far away, just far enough for 2.4GHz to not be enough.

Thanks for your input, makes me feel better

 

[workshop]

Paul,

You're well within safe limits and you'll run out of video long before control.

Designing a switching regulator or power supply is non-trivial. The only one on the market of any value is the Castle Creations 10A BEC.

People in this hobby LOVE to flame linear regulators and the guys who advocate them. One trades a little bit of heat for ZERO RF and that is worth all the so called loss. If properly designed, a linear regulated power supply won't make a noticeable difference in flight time but will add MILES to one's range. If you ask Trappy, you'll get 100% different answer.

Jeff

 

[kloner]

i agree with Jeff,,,,,,, not the ultimate, but well within range. That's why these big wings are so popular, easy to spread it all out...... my zephyrs are sub 95 all powered up......

Are you guys extending the antennas up and out of the waterproof quads?

the core has to be insulated if your all nutts about reception and makes the biggest difference on 5.8 video. otherwise, if your powering a video tx and cam, it can overheat within minutes if powered up and not flown. sucks in the summer, causes shearing, all kinds of problems. if the core is only powering a cam or simply used as a osd your fine insulating it. I've been 2 miles in my disco and with 4000mah had to land short and go get it. Your not talking about gang busters of distance, but again 5.8 actualy penetrates when you can really clean up the floor.

 

[Aerovideo]

Thanks guys, the reason I had posted about the noise was from reading over at the FPVLab site on people only getting 500m or so with their EZUHF gear. That had never happened to me before but now I have the TBS Core which appears to be the culprit a lot of times. And testing for the core lead me to the discovery of the noise from the Sport board.

I've only been out 1.25 miles with my quad and that made me REALLY nervous but I certainly didn't want to have failsafes at 500m either.

I do have a lot more noise on my video with my aquacopter but I attributed that to having the spironet antenna inside the frame with all the other electronics around it. Pretty tight fit. Not sure that these aquacopters were designed for FPV

Here are some pics of my setup if you're curious. I haven't sealed all the holes yet. I got rid of the landing gear though as it didn't work and made the video worse:

View attachment 10018View attachment 10026View attachment 10025View attachment 10024View attachment 10023View attachment 10022View attachment 10021View attachment 10020View attachment 10019View attachment 10027

 

[workshop]

Wow... Very neat... I love the way you mounted the EzUHF RX!

Mine is ocean going so the build requirements are a bit different. I'm hoping to make only ONE hole in the watertight compartment for 12 motor wires and antenna coax.

Jeff

 

[Aerovideo]

Ocean going, wow... would love to see your build!