Re: Regentone A133 HT smoothing capacitors, V4 cathode resistor
The EL41 (and its designed-for-series-heater-chain sidekick the UL41) is renowned for internal leakage that can put a positive bias on the control-grid, and give the excess-current effect you've noted.
Various people (myself included) have over the years tried a range of different ways of 'zapping' the conductive film within the valve that causes this leakage, and report different levels of success.
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