[Amps] al811h reverse grid current

jim.thom jim.thom@telus.net jim.thom at telus.net
Sun Feb 22 13:11:37 EST 2026


From: "gudguyham at aol.com" <gudguyham at aol.com>
To: Curt Nixon <radio.ku8l at gmail.com>, Kurt Cathcart
        <Kurt at kuhlroad.net>
Cc: <Amps at contesting.com>
Subject: Re: [Amps] al811h reverse grid current

>You did it wrong. ?The GDT do not replace the resistors on the grids. ?You
remove the resistors >and the caps to ground ?on each grid to ground on the
tube socket. ?You directly ground the grid. >?Then one GDT goes from  each
filament wire to ground. ?That?s the way it?s done.

Then also wire a 100K @ 3 watt  MOF directly in parallel  with each  GDT.
2 x GDT's required.  2 x 100 k resistors required.   GDT's are  160 V
rated.  Same as ameritron uses.

Jim   VE7RF


More information about the Amps mailing list