u/AtanasPrime

I built a Pulsar 9 frame with 2812 900kv motors and I’m trying to tune it, but as you can see from the pre-filtered gyro spectral analyzer on Pidtoolbox from above, there’s a lot of high frequency noise that I can’t seem to figure out. On top of it, the motors get hot very quickly, which I assume is related.

I’m running a T-hobby V70A ESC & F7 FC SE 6-8S 4IN1 Stack. It’s soft mounted with a 2200 uF 50V capacitor. Admittedly the cap leads on it were kind of long, so I threw a 1000 uF 35V capacitor with really short leads on the battery terminals (in parallel) to see if it would do a better job of filtering the high frequency noise, but it didn’t make a difference. I also made sure that no wires are rubbing against the gyro. At this point, I’m wondering if the motors I got are just wonky. They’re unbranded from Ali Express, but seem to have hundreds of positive reviews, so I didn’t think they’d be a problem.

Any thoughts on what could be causing the issue? Should I spend the $$ on more premium motors, or are there other things I should try before assuming it’s a hardware issue?

TIA!

Is anyone else disappointed that the economics of building your own drone don’t really make much sense? I’m still relatively new to the hobby and have only built a couple of drones, a 3” for running a single 18650 and a 9” designed to comfortably carry a 6s3p 21700 pack. I felt justified in buying the parts for and building these drones because there weren’t a lot of good bnf options fitting those particular parameters.

Now I’m looking into a 4” long range drone and finding it difficult to justify the cost of parts compared to available bnf options. Specifically, I can get all the parts I want for approximately $30-40 cheaper than just buying a Flywoo Explorer LR4. Sure, my build would have a true diversity receiver and arguably a better gps than the Flywoo, but other than that it would be more or less identical. And the Flywoo would probably be better put together and tuned, if I’m being honest. It just doesn’t seem worth it. And that’s without factoring the time I’d spending building and tuning rather than flying.

I’ve done similar calculations when it comes to building a tiny whoop. It just seems to make a lot more sense to buy one of the many bnf options out there unless you’re trying to make something unique. I find it fairly disappointing because in the ideal world I’d love to build more drones, but when I can’t justify the extra time not spent flying with at least significantly offsetting the cost, it makes justifying a build a lot harder.

High frequency noise and hot motors 2812 on 9 inch

Economics of building your own “standard” drone