[AMRadio] 100TH and 250TH advice and or comment


rbethman rbethman at comcast.net
Tue Aug 25 13:06:11 EDT 2009


Bernie,

That's my take on this too!  At least from past experience.

I'm just puzzled by the occurrence.  I doubt that there is 25 hours of 
actual plate power applied, I.E., key down.  I don't make the "old 
buzzard" routine talks.  I've always been in a round table, most being 
technical in nature regarding AM ops., equipment, and such.

I wonder if maybe these old tubes are at the point where a muffin fan or 
two ought to be added to the Old Gals.

Bob - N0DGN

Bernie Doran wrote:
> The milky white appears when the tube has lost its vacuum and fil power is 
> applied, I have seen this vapor of death more than a few times when testing 
> old fellows. This is not to say that this is the only reason for the white 
> deposits, but it is the only way I have seen it form. Bernie W8RPW
>   



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