In Reply to: Plate load choke needed posted by AstroSonic on May 22, 2004 at 14:16:24:
you say you need a plate choke for a 6J5--- and that the part spec'd in the original application was rated at 15ma/160H.
first thought is... generally a 6J5 will be run at less than 10 mils of plate current... the author of the circuit may have been using a 15 mil rated plate choke cause it was simply available to him....
so.... first see if you need the 15 mil rating....
here are several alternate plate chokes that we make... that would work well with the 6J5....
EX0-99 can be configured to handle either 10 mils or 20 mils of dc plate current. Inductance with 10 mils (two coils in series) is 750H. Inductance with 20 mils (two coils in paralell) is 187H.
EXO-010 10 madc of plate current and 276H of L. nominal dcr is 850 ohms. These units run at real low total flux density (ac and dc combined is less than 10kg). These units are rated at 245vrms at 20 hertz.
we can also regap the standard EXO-010 for 15 mils of plate current and then you would achieve 230H of primary L while maintaining the same AC max operating levels.
The EX0-010 is $75 each in channel frames and the EXO-99 is $99 each in channel frames.
this should have ya covered!!!