25-03-2019, 05:30 PM
I agree with Kalee20's analysis. At the time, interpin leakage wasn't seen as a problem, possibly not even known about. In any case UL41s were readily available and customers wouldn't have been surprised by the need for a new valve every now and then. AFAIK, Mullard labelled pin 4 as not connected, without any footnote to suggest that it shouldn't be used as a tie point. So why not use it if it's convenient.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
