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>
>> >-  During the entire time that the Plywood Box was in service, it 
>> >consumed less than 1 box of 5 fuses.  Rated screen dissipation was 275w 
>> > The fast blow fuse opened at roughly 200w.  
>> >
>> Yes, I see...
>> 
>> 73 from Ian G3SEK   
>
>Not according to the Littlefuse catalog. 
>
?  (the Littlefuse catalogue apparently discusses fusing of tetrodes with 
handles)
>It shows the fatigue life of fuses, time before opening under various 
>loads, and so on.
>
The screen fuse was selected so that it would open when the screen 
current exceeded the normal amount.  
>It is impossible to find a fuse that reliably holds at under 200 watts 
>of load, and opens within a minute at 275 watts of load.. especially 
>higher amperage fuses like a transformer primary would require.
>
Is this getting good or what?  
>Now you might get a fuse that is rated to safely carry 25
>watts of load 
Fuses are rated in amperes, not watts.  
>that opens in a reasonable time when the load is 250 
>watts or more.
>
>Fuses mainly prevent drastic melt-downs. 
[chortle]
>Electronic circuits are 
>much more reliable 
Transistors that C/E short offer zero protection. 
> and hundreds of times faster in most 
>applications.
Screen potential was 1200 - 1500 V.  Duhhh.  
end
-  Rich..., 805.386.3734, www.vcnet.com/measures.  
end
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