[AMPS] a sticky issue.

[Ian White, G3SEK]

measures wrote:

>Burning up a tetrode's screen from 
>>>mistuning is unlikely because screen supply power transformers usually 
>>>have fast-acting fuses in the primary.  
>>>
>>Can anyone think of a *worse* way to protect the screen of a tetrode?
>>
>Substitute a 20A slow blow fuse for the fast blow screen fuse?  Wrap 
>aluminum foil around an open fuse and reinsert in the screen fuse holder?

I knew you wouldn't disappoint me!

>-  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          Editor, 'The VHF/UHF DX Book'
                          'In Practice' columnist for RadCom (RSGB)
                           http://www.ifwtech.com/g3sek

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