Ok, I'm assuming that my original post was so far off regarding the compatibility of a PWM to voltage converter module - WS55-220 Brushless DC Motor Drive - 500w brushed spindle that no one wanted to tell me how stupid I was being? So I'm back for another go.......
https://www.aliexpress.com/item/3234...archweb201603_
Would I be correct in thinking that I could use an Arduino Uno with a PWM to voltage converter module with a brushed 500w spindle to achieve PWM control through Grbl? Apologise in advance for the state of the attached image!