Forum Discussion
wopachop
Jun 19, 2018Explorer
Got to play with the fans today. Nice and organized as you can see. Still waiting on the PWM motor speed controllers.
Tested the 4" blower and the 140mm 4 pin fan using my cheapo LED PWM dimmer. Which landYacht taught us is not the correct frequency. It produced a loud buzz on both fans. Also tried a little LED analog dimmer. That also produced a buzz.
Wondering why the little voltage dimmer does not work? I have some of those blue buck/boost voltage regulators as well, but need to find them. Was hoping my little dimmer knob would work like the dimmer that comes with the FM181.
Held off buying the 4pin Noctua PWM dimmer just to save 20 bucks for now. Will get one eventually. Plan was to do voltage dimming on the 140mm fan but thats not working out.

Tested the 4" blower and the 140mm 4 pin fan using my cheapo LED PWM dimmer. Which landYacht taught us is not the correct frequency. It produced a loud buzz on both fans. Also tried a little LED analog dimmer. That also produced a buzz.
Wondering why the little voltage dimmer does not work? I have some of those blue buck/boost voltage regulators as well, but need to find them. Was hoping my little dimmer knob would work like the dimmer that comes with the FM181.
Held off buying the 4pin Noctua PWM dimmer just to save 20 bucks for now. Will get one eventually. Plan was to do voltage dimming on the 140mm fan but thats not working out.

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