There is a “field test” that you can do to check your ultrasonic
cleaners performance. It is called the “foil test”. Simply put, you
take a piece of aluminum foil approximately 1 inch shorter than the
long axis of your tank and long enough to be able to reach about 1/2
inch from the bottom while you are holding the sheet. With the machine
running immerse the aluminum foil vertically into the tank until it is
about 1/2 inch from the bottom and not touching the ends/sides of the
tank. Time the run cycle for 30 seconds and remove the foil from the
ultrasonic. You should see a pattern of dents and /or holes evenly
distributed on the foil. If you find the pattern is asymmetrical or
non existent you have an indication that the machine is not
functioning properly and should be sent for repair. As you know Lone
Star Technical Services specializes in the repair of ultrasonic
cleaners. We use this test daily and it has proven an effective
indicator of a units function. If indeed your unit is in the 80 kHz
range you will be pleased to know that it will probably "outclean"
many of the more modern units on the market. As john states the
buzzing noise is just telling you that the machine is on and is
probably happily doing its “ultrasonic thing”. Try the foil test.
Mike & Dale
Lone Star Technical Services
The ultrasonic repair guys. “If you don’t need us today we’ll be here tomorrow”