Nothing wrong with that! You can go to just grid leak bias with the 811a's, or 572b's. 812a's are THEORETICALLY supposed to me better under modulation, but I could tell no difference in peak modulation, distortion, etc, between the 811a and 812a tubes (with plenty of grid leak bias).
Brett N2DTS -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Robert Nickels Sent: Wednesday, September 29, 2004 9:04 AM To: Discussion of AM Radio Subject: Re: [AMRadio] Home Brew > If I were going to build with tubes again and two hundred watts was > the carrier output that I wanted. I would use a pair of 812s in push > pull class C and modulate with a pair of 811As push pull class B. I have parts of an old homebrew 10 meter AM transmitter and it looks like this is what he did too, only using 811s in the finals as well as modulators. Probably the simplest/cheapest way to get some power back in the early 50s. 73, Bob W9RAN ______________________________________________________________ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net