807 Testing.

[Diabolical Artificer]

Thanks for that link Andy. The 807 with an OC heater was of inferior construction in comparison to others I have. The mica spacers were thinner, there were no ceramic spacers for the anode , the anode was made of thinner steel, there was no ribbed "clamp" under the anode and lastly the getters were simple bars of some dark metal, not the usual dish. It was a JAN valve which I think stands for Joint Army Navy, so intended for military use; you would of thought the standard to be higher.

I'll chuck the runaway 807 in an amplifier and check for oscillation, however my homebrew tester does have ferrites on all valve base pins, one ferrite in the anode cap and other anti oscillation measures.

Andy.