I say try it and see how it works. I have doubts tho, with two different transformers, you will have different phase shifts and two different frequency responses.
What is wrong with the choke setup? I have used that setup on a number of rigs and had good positive modulation. I have had worse results with the resistor setup. Some tubes like the 4cx250b don't have normal screen current curves, and you HAVE to use a mod transformer to modulate the screens. I don't know of any other tubes offhand that NEED the separate winding for the screens. I used to have a 30K1, and blew out the mod transformer. The original transformer had the screen taps, the new setup used a choke, no difference between before and after as far as modulation percentage, the rig sounded better because of a better bigger mod transformer. I am big on trying things, you learn something every time you try something, even if it does not work. Brett N2DTS > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of patrick jankowiak > Sent: Sunday, November 30, 2003 2:39 AM > To: [email protected] > Subject: [AMRadio] Modulation of the screen grid > > > Would anyone mind looking over the schematic at the web page below and > see if I am on the right track to modulate the G2 voltage of > a 4-1000? > > This should provide the 250 volt peak voltage necessary for the screen > grid, and then I won't have to rely on using just a choke from the > screen supply or a dropping resistor. > > Basically I plan to use a smaller mod xfmr to couple some of the > modulated plate voltage to the screen. > > Maybe I have some mistakes in the parts or signal level values, but I > think it should be right. > > Thanks in advance, > Patrick > > http://208.190.133.201/mod001.gif > _______________________________________________ > AMRadio mailing list > [email protected] > http://mailman.qth.net/mailman/listinfo/amradio
