[Heatercathodeshort]

The A1 supply [pin 10 of CRM172] is fed through a 680K resistor but strangely no decoupling capacitor. The DC side of the U25 should produce a 'crack'. It will make you jump the first time you do it so I think the U25 is duff. The strange smell is OZONE caused by chemical brakdown of air by electrical discharge[?] The ion trap is nothing like as critical with Mazda tubes but will cause screen black out if a long way off. Pictures here of a T330. Almost identical electrically. Shows ion trap position with yellow sleeve to bottom. The other is roughly what you are aiming for. Getting there Colin. Regards, John.