[Amps] slow down circuits for 240v blower

[Neil Carr G0JHC]

I'm wanting to fit a front panel control  on my latest amp project which
will allow me to reduce the speed (and noise) of my EBM blower, (G2E-140)
especially during long periods in receive.

 

This doesn't have to be anything clever that monitors temp or slows
down/speeds-up when keying/unkeying the amp (but I would consider something
if simple to construct), But nothing more than an inductive control. I have
of course already made the mistake of trying a number of off the shelf house
hold items (that were resistive, silly me), and also have a 240v ceiling fan
control board, which for some reason, although works fine, produces a heavy
hum on the motor? My simple  varibale Variac does a great job. 

 

Whats out there please!?  or how do i get rid of the hum on ( a number of
fan speed controls I've tried)

 

Any guidance appreciated.

 

73 Neil G0JHC