An 807 would probably oscillate cathode driven due to the fact that the
suppressor (beam forming plates) are
connected to the cathode internally thus providing a lot of plate to
cathode capacitance. The choice of going
to grid driven is not bad at all.
73
Bill wa4lav
At 10:29 PM 3/16/2003 -0500, you wrote:
>----- Original Message -----
>From: "Bill L. Fuqua" <wlfuqu00@uky.edu>
>To: <garyschafer@attbi.com>
>Cc: <amps@contesting.com>; <n1rj@pivot.net>
>Sent: Sunday, March 16, 2003 6:45 PM
>Subject: Re: Re: [Amps] Membership
>
>
> > Unfortunately there are a number of hams that came up thru the CB ranks
>
>Yes, I'll confess to that...some 30 years ago. All my CB buddies, building
>GG sweep tube amps, told me that anything grid driven would be unstable,
>oscillate, and just be unusable. That was just the motivation I needed to go
>ahead with building a four 807 amp. They were right, it was quite the
>oscillator. Then I learned about neutralization and parasitic suppressors.
>Soon those 807's were running smooth as silk. At the time I was working on
>my ham ticket, but CB was there and it was a place to experiment with RF.
>Once I got my ticket I traded the amp for a 50' tower, but I sometimes
>wonder what ever became of that amp. It was a beauty...there is something
>about 807's...a romantic type something...
>
>Jeff - K1LE - CT ><>
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