[AMRadio] Amplifier with input drive to screen grid


Bill Fondren bill.fondren at sbcglobal.net
Tue May 23 08:43:55 EDT 2006


I recently traded for a linear that has a strange input circuit, at least to me.  The amp is built in a 18 " Bud rack mount cabinet weighting about 150 lbs.  To heavy for 1 person to handle so I deceided to split the RF deck from the power supply and put it in a taller cabinet along with the exciter.  No info was with the unit.  I have used it a couple of times and it works fine .  It uses a pair of 813's in parallel.  I started to draw out the circuit finding that the drive goes to a tuned circuit and then to the sceen grids of the 813's.  The control grids are connected together and go to a 10K resistor, the grid current meter and then to grd.  No connection to the drive circuit at all other than the interelectrode cap. I guess.  The plate circuit seems to be normal.  Just wondering if any one has seen something like this before.      Bill     K5PML


More information about the AMRadio mailing list

This page last updated 11 Dec 2017.