Reduce transducer power for ultrasonic bath?

[smilem]

Hello, I would like to reduce transducer power for ultrasonic bath.

1. I could use analog simple wirewound pot I think.
I would have to measure amps, volts, then see what power pot I need. This would allow to pass the 25Khz signal to transducer unaltered right?

2. I could use some sort of fancy electronic control with nice display for volts, but what?

If they would hold the power needed would the controls like this work:

http://www.ebay.com/itm/Adjustable-...al_Components_Supplies_ET&hash=item1e82527f23
http://www.ebay.com/itm/NEW-5V-30V-...923?pt=LH_DefaultDomain_0&hash=item19e08df07b

Would I still get the 25Khz output to the transducer?

 

[Laplace]

Whether a wirewound pot would work depends on the type of oscillator and transducer used. If it is a ceramic crystal transducer and resonant oscillator circuit that depends on the phase shift of the crystal at resonance, then introducing a wirewound resistance in series with the crystal may change the characteristic impedance at resonance so that the oscillator will then fail to perform. However, if the oscillator is operating independently from the transducer and driving an amplifier that powers the crystal, then your idea is likely to work.

 

[smilem]

The model is Proclean 507, how do I know if it is

1. ceramic crystal transducer and resonant oscillator
2. oscillator is operating independently from the transducer

 

[smilem]

Here are the photos, what a shocker they (ulsonix) assembled it very dangerously.

Should I clean the flux even more?

Photo01, very dirty PCB.
http://i.imgur.com/nme7BXL.jpg

Photo02, dangerous assembly
http://i.imgur.com/9MnLxCo.jpg

Photo03, Back of PCB
http://i.imgur.com/l4d3kL5.jpg

Photo04-09 PCB (should I clean it even better?)
http://i.imgur.com/QTwWi7z.jpg
http://i.imgur.com/5oeXFLL.jpg
http://i.imgur.com/63sY48P.jpg
http://i.imgur.com/NiQuyXE.jpg
http://i.imgur.com/hPgr3YS.jpg
http://i.imgur.com/Fb5gyLE.jpg

I added insulation to the bottom
http://i.imgur.com/wik2cqm.jpg