THE GREAT MULLARD MAGIC BLOG — bright emitter valve

Back in the dim & distant past, in a land far away, shrounded in the mists of time there was a valve................... and what a valve, not like the ones we have today, oh no, it was very different indeed.     At the time, it was very similar to all its contemporaries - not that there were so many -  and like them,  it was a general purpose triode having a four volt pure tungsten filament which operated at a temperature similar to that of an incandescent light bulb.  The electrode cage was mounted an an inverted pedestal sealed...