So i have a Aikon AK32Pro 4-in-1 50A 6S https://www.aikon-electronics.com/index.php?id=38
I bought it mostly becouse i wanted a 20x20mm with decent amp rating and Aikon makes "bulletproof" esc i have heard.

I noticed it said "up to 96KHz pwm" when i bought it but i did not think anything of it more than it seemed like a quality esc.

What i discovered is that in Blheli32 configurator i can only choose 48KHz and 96KHz?
Is there some way of doing 24KHz? I mean it seems kind of strange that it cant do slower. Whats the problem that makes it unnable to do 24KHz?
I have flashed latest v32.8 and it is still same.

I also saw when Joshua Bardwell built his racer he could only choose 48 or 96KHz on the ESC he had whatever brand it was but it was after i bought mine otherwise i would have known it could be an issue.


Reason of wanting 24KHz is better braking. I can live with 48KHz but would be nice if i could try 24.

Anyone know if its possible?

*edit* Should have posted in the software section. Mayby Admin can move it.

BLHeli32 is licensed/closed source and the firmware is compiled based on recommendations by the manufacturer.

No way to unlock 24 khz on the board unless you can convince the BLHeli32 guys to do it for you.

There has to be a strong reason why the board is limited to the lowest 48 khz for pwm frequency.

Here is an example where 24 khz PWm frequency was enabled on the Holybro Tekko32 F3 40A 4-in-1 ESC using some test half pwm firmware by the BLHeli32 development team: https://github.com/bitdump/BLHeli/issues/488

(02-Jul-2021, 04:57 AM)kafie1980 Wrote: BLHeli32 is licensed/closed source and the firmware is compiled based on recommendations by the manufacturer.

No way to unlock 24 khz on the board unless you can convince the BLHeli32 guys to do it for you.

There has to be a strong reason why the board is limited to the lowest 48 khz for pwm frequency.

Here is an example where 24 khz PWm frequency was enabled on the Holybro Tekko32 F3 40A 4-in-1 ESC using some test half pwm firmware by the BLHeli32 development team: https://github.com/bitdump/BLHeli/issues/488

Thank you, thats interesting! After reading some answeres in the blheli32 rcgroups thread i thought it was impossible but mayby i could ask for a special half PWM code.
No harm in asking. Great find!

I requested a custom hex with 24Khz and a few hours later it was uploaded!
Only benchtested so far but seems to work fine. Good support for sure. I would have expected a few days atleast.
Rebuilding my quad into a lightweight 7" freestyle quad so motor braking is going to be important to not feel floaty.

Can you please post a link to your GitHub request because it may help others who would also like the same.

I found the request Myman made on github: https://github.com/bitdump/BLHeli/issues/538

One thing to note is that test codes are not compiled for all versions and so it should be considered a once off solution. Unless you keep asking for an updated version.

Let us also not forget that this is not considered an official version and so the hex can be deleted from github in the future.

And I am not sure if the dev's will entertain every request.

So if someone gets comfortable tuning and flying their quads using test code BLHeli32 firmware then be prepared to re-tune in the future.

Hopefully the dev's include half pwn option as an expert mode in BLHeli32

(03-Jul-2021, 10:52 AM)kafie1980 Wrote: I found the request Myman made on github: https://github.com/bitdump/BLHeli/issues/538

One thing to note is that test codes are not compiled for all versions and so it should be considered a once off solution. Unless you keep asking for an updated version.

Let us also not forget that this is not considered an official version and so the hex can be deleted from github in the future.

And I am not sure if the dev's will entertain every request.

So if someone gets comfortable tuning and flying their quads using test code BLHeli32 firmware then be prepared to re-tune in the future.

Hopefully the dev's include half pwn option as an expert mode in BLHeli32

Yes i also contacted Aikon so if they can manage to make something offical it would be better. Hopefully we can have full range 24-96khz in the future. Dont know why the range is limited?

To complete the thread i can inform that the esc flies fine on 24Khz on my 7" build. No strange behavior or anything.

With the newly discovered bug in Blheli 32.8 that renders RPM filter in betaflight pretty much useless i asked for an update to the new code and a few hours later he fixed it.
Very happy with the fast response!

https://github.com/bitdump/BLHeli/issues/546

Yes, I have heard a few reports on 32.8 causing issues with RPM filtering and the advice was reverting back to 32.7.

BLHeli_32 is closed source and licensed on 32 bit ESC’s and its great the developers are doing quick bug fixes.