I've picked up one of these and trying to get it to work. No output at the terminals, nothing when I try to arc. Leads seem fine, have checked the thyristors with a multimeter and seem to be working fine, transformer hums away, fan constantly on and I have a 13a fuse in the plug. Other than the board I'm not sure what could be the problem, I have checked the board components best I can with a multimeter but everything I test checks out - I'm not an electrician so might have to just take the whole thing to a shop. Having another look this weekend. Any thoughts before I do? In addition - when I got it there was a brass fuse in the plug and the capacitors on the thyristors had blown. I've replaced the capacitors with modern equivalents and a new 13a fuse.