05-21-2016, 08:43 AM
Hi John,
I took a look at the diagram for and it looks to be a good set. Containing a RF amp, separate mixer and osc tubes, one IF stage, A beat frequency osc, high gain 1st audio stage, parallel 76 driver tubes, and p/p 45's in the output. I'm a little surprised that it's using 45 tubes by 1935 they where getting long in the tooth. Also they require there own 2.5v filament winding all the others at 6.3v. If it was a Philco it would have p/p triode connected 42's. No need for the 2.5v winding. THe spkr is a little different than most in that the field coil is tapped and it's connected to the negative leg of the power supply so the resistance of the coil determines the bias for the 45's. Without the original spkr field can be replaced with a few high wattage resistor. Pray the power transformer is good for a rewind will$$. Finding one would be difficult.
Terry
I took a look at the diagram for and it looks to be a good set. Containing a RF amp, separate mixer and osc tubes, one IF stage, A beat frequency osc, high gain 1st audio stage, parallel 76 driver tubes, and p/p 45's in the output. I'm a little surprised that it's using 45 tubes by 1935 they where getting long in the tooth. Also they require there own 2.5v filament winding all the others at 6.3v. If it was a Philco it would have p/p triode connected 42's. No need for the 2.5v winding. THe spkr is a little different than most in that the field coil is tapped and it's connected to the negative leg of the power supply so the resistance of the coil determines the bias for the 45's. Without the original spkr field can be replaced with a few high wattage resistor. Pray the power transformer is good for a rewind will$$. Finding one would be difficult.
Terry
