I was about to pull my Red Tremor out of my MET Pro and sell it until I installed the Pulse-Width-Modulated (PWM) controller. Thanks to the OP and all others that posted with installation help.
Prior to the PWM controller I tried:
- Moving the center of gravity of the counter weights closer to the shaft (my weights had two through holes both threaded for the lock nuts). A minor improvement.
- Adjusting the weights about 90°, 135° and 170° apart. I found a sweet spot between 135° and 170° apart which seemed to work fine during the coil test but the shaker was still too strong for my taste during the full Sparky zapping.
I have the pin on a concrete floor and it felt like Red Tremor was vibrating the machine across the room.
The controller was best $1.97 (including shipping, arrived from China in 15 days), I've spent on ebay (http://goo.gl/3SmRPG). Listing is/was "1pc New PWM DC 6V/12V/24V/28V 3A Motor Speed Control Switch Controller" and the seller was "cell.expert"
The Red Tremor is much better behaved and feels closer to a stock Stern version although it is slightly louder (The picture shows the temporary mounting with earthquake putty).
I'd use this combination again in the future on another shaker enabled machine.