I decided to work him with 100 watts while the linear was warming up. He came back 'EI2?' after my first call! I gave him the call twice and he came back 'EI2C?' and before long, I was in the log!
This is the same operator (JA1PBV) that gave me VK9XS, Christmas Island, within the past week. The hexbeam is working beautifully. I have nabbed FIVE new DXCC in a fortnight, all five of them in the Pacific/Oceania area. Brilliant. Really delighted.
Below is a video showing the signal from VK9CS just after I worked him.