[Amps] Dimished Tube Life

[Dave white]

The answer at least made me laugh,

As everyone is now saying, there are a zillion variables in play so it's a bit of an impossible question.

What filament voltage? Filament soft start? Ht? Cooling? Stability? Manufacturing variances in tube? Manufacturer? New or rebuild? Air temperature? Air humidity? Blower runs after you switch off? Do you drive the amp? Bt how much? What frequency? How well tuned? Good smoothing capacitors? Well regulated filament? Bias? Etc etc

So maybe 4 hours isn't such a flippant answer after all!  Personally if asked such a vague question I'd give a vague answer: something between just above zero and 'lots'.....

Cheers
Dave G0OIL

-----Original Message-----
From: Gary Patterson <gpatterson53 at hotmail.com>
Sent: 25 September 2009 09:11
To: amps at contesting.com
Subject: Re: [Amps] Dimished Tube Life


"What a Crap answer"  ...... What a thoughless response.  Clearly, with the data given, as we take the limit of N with respect to tube usage the answer of 4 converges as the only logical answer.


 
> From: noddy1211 at sbcglobal.net
> To: amps at contesting.com
> Date: Thu, 24 Sep 2009 21:20:29 -0700
> Subject: Re: [Amps] Dimished Tube Life
> 
> What a Crap answer, in reality nothing that you could even measure, don't
> even worry about it
> 
> Mike
> 
> -----Original Message-----
> From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com] On
> Behalf Of Gary Patterson
> Sent: Thursday, September 24, 2009 8:02 PM
> To: amps at contesting.com
> Subject: Re: [Amps] Dimished Tube Life
> 
> 
> 4 hours
> 
> > From: mhughes149 at verizon.net
> > To: amps at contesting.com
> > Date: Thu, 24 Sep 2009 22:43:13 -0400
> > Subject: [Amps] Dimished Tube Life
> > 
> > Hello all !
> > 
> > I wonder, and I hope someone can offer a reasonable explanation. If I turn
> on my AL 1500 Amplifier, which uses the 8877 indirectly heated cathode tube
> when I come into the shack and then 4 hours later, I turn off the amplifier
> and go about my business, how much have I shortened that tubes' life ?
> > 
> > KE9AG
> > 
> > Mike..
> > _______________________________________________
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> > Amps at contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> 
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