[Amps] Switching PS for filaments?

[TexasRF at aol.com]

I'll get back to you in about 10 or 20 years and let you know if there have  
been any more filament failures.
 
Tubes are expensive enough that I will spend the $10 to protect them even  if 
it is an imagined protection. Hell, I would surround them with hog hair if I  
thought it would make them live longer!
 
Using your logic: I know they failed due to a defect how? I don't.
 
73,
Gerald K5GW
 
 
 
 
 
In a message dated 2/18/2007 11:48:31 A.M. Central Standard Time,  
w8ji at w8ji.com writes:

> It  may be 1 in 1000 but if you are the 1 you might well 
> think the number  is
> 1 in 1. After loosing the filament in a couple of 8877s 
>  and a TH347 over the
> years, I have become one of the  fanatics!


.....and you know the filament would NOT have failed  anyway 
in that 1-in-1000 case WITH protection in that same tube  
because ......????

Sometimes, like it or not, things just fail  because they 
have a manufacturing defect. That sometimes triggers us into  
finding a pathological cure.

That's certainly OK so long as we know  we are leaping to 
conclusions. :-)

Of course it is a good idea to  not use a transformer and 
wiring that can dump 100 amperes into a 10 amp  filament, the 
question is what really caused the failure.

73  Tom