Hello all,
After finding this out, I looked in my 1990 ARRL handbook and found a
construction article on building a 2 meter 4cx1000 amp using this
technique. The text went into some additional detail.
Those who care can read it.
If anyone is contemplating building something like this, let me know, I
have the socket.
73 de Steve, NJ4F
At 11:39 AM 1/12/98 -0700, John Lyles wrote:
>RE: NJ4F's Y131A Eimac socket.
>
>The Y131A is similar to SK800B, used for 4CX1000A, 4CX1500B. However, it is
>for Grounded Screen application, and has no built in screen bypass like the
>800B has (1.5nF). Collins and now Continental Electronics used to use hard
>grounded screen for similar tubes and for the 5CX1500A in their FM
>broadcast rigs. They float the cathode (filament transformer is isolated
>for screen voltage) and apply negative potential there, to do the same
>thing. Of course this means the grid bias has to be somewhere even more
>negative than the filament bias, so that power supply is usually tacked in
>series there.
>
>By hard grounding the screen, the tetrodes give better isolation (grid to
>plate feedthrough) for VHF. This eliminated some of the hurdles of
>neutralization, but it still is advisable. It makes the screen bypass go
>away, and leaves only cathode bypassing for the designer to contend with.
>
>K5PRO
>John
>
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>--
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>
>
---------------------------------------------
Steve Bookout, NJ4F
Rapidan Data Systems
'DX4WIN...The way logging programs should be!'
Free demo at http://www.erols.com/pvander
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
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