-- forwarded message, please reply to sender and MMD --

Hello, I am Mario Solimbergo from Italy and I have a Duo-Art Weber
piano built in England in 1923.  The player piano is equipped with a
steamboat pump.

I have a problem on the regulation of the motor speed.  The motor
governor changes the speed, but this regulation is not linear.  With a
little movement of the speed indicator (for example, from 10 to 50) the
speed of the motor changes from 10 to 140.

I have tried many calibrations of the system without obtaining the
goal.  Why?  Is it a spring problem, a pump problem, or something else?
Can you help me?

Best Regards
Mario Solimbergo