[NV3G]

I am presently working on a Sears Model 1708 radio. It has a dual potentiometer of which 500K is the volume control and 1K is the variable cathode resistor for the RF ( 78 ) tube and the Oscillator/Detector tube ( 6A7 ). I do not understand this type of design. What did the engineer have in mind? How does it work when your increasing the volume control for audio and decreasing the cathode resistance in the cathode circuits of the RF and Oscillator/Detector Stages?

Any help would be greatly appreciated and where do I find a replacement control? Perhaps a modification is in order.

I am confused.

Thank you,
nv3g