Omid, I thought I had already addressed this earlier in this thread. A variable frequency drive coupled with a rewound or a new motor is the only way to get your desired speed. along with being dangerous a variac WILL NOT WORK AT ALL with the type of motor in your santos and a transformer will not slow it down enough. Again, if you use a variac the speed of your mixer will not slow down at all and you will just eventually damage the motor. Please save your money. plus, I am a little scared.....who are these experts you are talking to.......they are giving you bad advice. Remember, I am a santos owner...been down this very same road years ago. If you don't believe me hopefully scpizza will talk to you soon so you can stay away from the advice of people speculating about how your santos works.
Dear Scott, I thank you boundlessly for your concern and guidance. Electronics—at the macro level that concerns the Santos mixer with its seemingly simple circuitry—should not be a matter of guesswork and groundless solutions
for an electronic engineer who graduated from the University of Berlin, where he also taught electronics for several years. Besides, he worked many years for Grundig
as an engineer. So, I am truly puzzled and perplexed as to how he miscalculated, if at all, his solution to the problem. Perhaps he may change his mind once he takes a close and personal look at the inside of the mixer. He did tell me not to try anything until he is back from Germany. So far, all he has seen are the schematic and the specification sheet, as illustrated hereunder. Either those who tried the above-referenced route or solution did not do something right or the engineer is missing crucial pieces of information or he is simply incompetent! I will probably give him a call tonight in Germany. Dear Scott, again, I thank you for your help.