[sdiy] heater voltage: how much is too much?

[DON'T CC ME PLEASE!"Roy J. Tellason"]

On Sunday 13 August 2006 07:48 pm, anthony wrote:
> The only thing that made me wonder is the fact that the 50L6 is VERY hot to
> the touch - compared to the 12SQ7.

Well,  let's see...

The 12SQ7 has a heater rating of (nominally) 12.6V at 150mA.  That's 1.89W.  
The 50L6,  OTOH,  has a heater rating of 50V at 150mA.  That's 7.5W.  Almost 
four times as much.

Yeah,  I'd say it would tend to feel a little hotter.  :-)

Perhaps this page (and the attached datasheets) may help some:

http://classiccmp.org/rtellason/tubes.html

?

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