I have a 2 qt Sonix IV Ultrasonic Cleaner that has a very weak
cavitation. I tried the aluminum foil test and it only produced one
perforation in a 10 minute span. I also observed that it only raised
the water temp about 8 degrees with the heater off.

What's the most likely scenario? I would assume the semiconducters
are OK since it does produce some cavitation? Do transducers
gradually weaken over time? Could a leaky cap. distrub the
oscillation reducing the units performance?

If it was DOA the diagnosis would be easier but what causes these
units to weaken?

Thanks

On Nov 27, 7:53 am, bud wrote:
I have a 2 qt Sonix IV Ultrasonic Cleaner that has a very weak
cavitation. I tried the aluminum foil test and it only produced one
perforation in a 10 minute span. I also observed that it only raised
the water temp about 8 degrees with the heater off.

That doesn't spell "very weak" to me, but maybe I'm just clueless.
The innards of these cleaners have two features that can result
in lower output:
(1) mechanical coupling of ceramic ultrasound transducer to
the tank is through a high-tech glue blob, so if that glue cracks, the
transducer vibrates 'free'.
(2) Often the oscillator has a tuned circuit that acts to impedance-
couple the transducer. Tuning can change over time.

I've used some hotmelt adhesives for ultrasound, but I presume the
transducer coupling is epoxy-like, so it can't be easily fixed.
Inspect
and if it's bad, consider rebuilding options. If it's the transmatch
network, I've seen adjustment options (use a PLASTIC driver to
turn the ferrite screw); an AC current meter will indicate extra power
drain if you are increasing the power transfer to the water that way.

whit3rd writes:

On Nov 27, 7:53 am, bud wrote:
I have a 2 qt Sonix IV Ultrasonic Cleaner that has a very weak
cavitation. I tried the aluminum foil test and it only produced one
perforation in a 10 minute span. I also observed that it only raised
the water temp about 8 degrees with the heater off.

That doesn't spell "very weak" to me, but maybe I'm just clueless.
The innards of these cleaners have two features that can result
in lower output:
(1) mechanical coupling of ceramic ultrasound transducer to
the tank is through a high-tech glue blob, so if that glue cracks, the
transducer vibrates 'free'.
(2) Often the oscillator has a tuned circuit that acts to impedance-
couple the transducer. Tuning can change over time.

I've used some hotmelt adhesives for ultrasound, but I presume the
transducer coupling is epoxy-like, so it can't be easily fixed.
Inspect
and if it's bad, consider rebuilding options. If it's the transmatch
network, I've seen adjustment options (use a PLASTIC driver to
turn the ferrite screw); an AC current meter will indicate extra power
drain if you are increasing the power transfer to the water that way.

The transducers can also crack.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

Thanks,
I did another foil test last night and I do think this unit is
probably working properly. I saw about 20-30 small perforations form
over a 10 minute cleaning cycle. Maybe I missed them the first time
because they are very tiny. Once I hold the foil to a bright light
they become obvious.

The transducer ohms out as infinity and looks solidly attached to the
tank and I see no cracks or other damage.

I'll take another look tonight but I don't recall seeing any tuning
adjustment on the circuit board.

bud wrote in message
...
Thanks,
I did another foil test last night and I do think this unit is
probably working properly. I saw about 20-30 small perforations form
over a 10 minute cleaning cycle. Maybe I missed them the first time
because they are very tiny. Once I hold the foil to a bright light
they become obvious.

The transducer ohms out as infinity and looks solidly attached to the
tank and I see no cracks or other damage.

I'll take another look tonight but I don't recall seeing any tuning
adjustment on the circuit board.






What was the thickness of Al foil, as measured on a micrometer ?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

On Nov 29, 1:02 am, "N Cook" wrote:
bud wrote in message

...



Thanks,
I did another foil test last night and I do think this unit is
probably working properly. I saw about 20-30 small perforations form
over a 10 minute cleaning cycle. Maybe I missed them the first time
because they are very tiny. Once I hold the foil to a bright light
they become obvious.

The transducer ohms out as infinity and looks solidly attached to the
tank and I see no cracks or other damage.

I'll take another look tonight but I don't recall seeing any tuning
adjustment on the circuit board.

What was the thickness of Al foil, as measured on a micrometer ?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list onhttp://home.graffiti.net/diverse:graffiti.net/

It's freezer foil and it measures .0015"