Guys, we have a project wherein we need to use a 40kHz ultrasonic transducer to penetrate through a 4-inch thick of a fresh concrete mix. we are using a 40kHz ultrasonic transducer rated to work up to 50 watts. do you guys know any working schematics for such an amplifier? we saw some drivers in the net and can be bought around $50 but due to time constraints we cannot order abroad and wait. we are from the philippines.

 

you could use a bridge output using a TDA2040 chip as on page 8, they will work upto 100Khz, to alter the gain change R3/4 and R5/6

 

There is a lot of overlap in circuits that do the same things while accomplishing different tasks. Radio, Magnetic Induction Heating, Ultrasonics; have a lot of common circuit components.

You will need a Frequency Driver, MOSFET Gate Driver, Power Amp, and Speaker. If you look at the end of this thread for Magnetic Induction Heater, you would change the CRYSTAL to match your frequency, and instead of operating an INDUCTION COIL, you would replace it with a Speaker.

http://forum.allaboutcircuits.com/showthread.php?t=94696

 

Why the choice of ultrasonics in wet concrete?

Generally a low frequency vibration is used to agitate concrete as it is too absorbent of the high frequencies and they will not penetrate, or do much at all.