Bill, assuming you want to use it as a linear, you should keep it as-is and work out how it is producing control-grid current like that. I have to think that the screens are tied to the control grids somewhere.
Bacon, WA3WDR ----- Original Message ----- From: "Bill Fondren" <[EMAIL PROTECTED]> To: <amradio@mailman.qth.net> Sent: Tuesday, May 23, 2006 5:04 PM Subject: [AMRadio] Re - response to input to screen grid amplifier > Thanks for the quick response to my questions concerning this amp. John, I > was ready for some salty remarks (hihi) and I did clean my glasses and take a second or third look at the thing. I thought I had missed something since going to USAF Radio School in the early 50's. Guess that tells u why I mess with vacumn tube rigs. Anyway thought I better get some expert opinions before starting to cut and chop to get it to a more conventional type. The construction of the amp is above average for a homebrew rig. A couple of other things There is a RFC choke coming off the G1 connections going to the 10K resistor then to the grid meter (0-30ma shunted with a 50 ohm 10 watt resistor) It does read about half scale peaking normal as u tune the grid circuit. Also a .01 bypass cap at the meter. The input coil is grounded in the middle through a RFC choke making a double coil, tuned by a split stator cap. One of the tuned circuits goes directly to the screen grids and the > other feeds the neutralizing voltage back to the input from the plate. No > bias circuits of any kind. The few times I used it I got good reports using a Elmac AF-67 exciter. Will probably change it to a more conventional type. Thanks again Bill K5PML > > > ______________________________________________________________ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb >
