Electromagnetic acoustic transducer (EMAT) proof-of-concept project.

Properly assembled circuit requires no fine tuning and works as expected after first run, providing  300V output. After assembling 2 more rectifiers we've got 924V output voltage.

We need a high voltage power supply. I am going to use DC/DC 12 to 300V boost converter schematic based on UC3843. Fig. 1. UC3843 based 12 to 300V  DC/DC  up-converter. To achieve even higher voltages I am going to use 3 identical secondary coils instead of one. This would give us 3 x 300 = 900V. Although it is less than 1200V used in original design I think we can start with this voltage. Special bobbin has been designed and 3D printed to incorporate 3 secondary coils. Coils are separated to avoid insulation breakdown. Fig. 2. 3D-printed bobbin for EFD25. Each secondary coil should be a accompanied by separate rectifier diode, RC snubber and output capacitors of course. The PCB has been designed in a way that all these elements are placed together inside a dashed rectangular area. So I don't have to order additional PCB from the factory, I can simply cut it from those PCBs that I already have.

I've made a high voltage bank. It consists of 5 WIMA FKP1 0.068 uF 1600V capacitors and six P600S diodes. Total capacity is 0.34 uF.

First I am going to copy  Experimental Demonstration and Circuitry for a Very Compact Coil-Only Pulse Echo EMAT