8005

[k4kyv]

I found mine, a lot of 5, in a box of miscellaneous junk in the floor at Young's Engineering in Salem MA in about 1975.  I think they charged me less than $10 for all of them.  One tube had an intermittent filament-grid short, I just recently dropped one and ruined the filament, but still use the others.  Since then I have acquired another NOS pair as a spare.  They are also good, but don't seem to quite have the modulation linearity that my originals have.

The plate appears to be made of the same material as that of 833A's.  As with the latter, it is very easy to overheat the plate and burn in a shiney spot, but that doesn't seem to affect the operation of the tube in the slightest.

[WA1GFZ]

One of out pubes looks like a mirror on one side of the plate. It is in use today so guess the thing is going to hang in.