Emerson radio from 1933 restored and upgraded.

[LW1DSE]

About a year ago I restored and modified this 1933 receiver. It came to me in catastrophic state. All components semi-destroyed, the cone of the loudspeaker, broken. Fortunately OPT, field and moving coil were OK.

This is a set similar to mine. I found the original schematic for 110V.

The chassis completely cleaned.

All components were discarded.

The loudspeaker, filter choke and RF coils tested OK.

Wire leads from both IFT replaced, and coils measured OK.

 

[LW1DSE]

Rewiring with new cable, the heater string.

Heaters fired alone. All OK.

The electronic wiring started. The 4uF will replace the heater droping resistance in order to lower the heat inside the cabinet. No DC power lines here anymore.

Still more new components. Oscillator coil at first plane.

 

[LW1DSE]

Upside grids wiring.

Repaired reconed loudspeaker again in its site.

Field coil and output transformer primary wired in a terminal strip (not original).

The wood cabinet restored too by a carpenter.

 

[LW1DSE]

The radio finished, with new knobs (original was missing).

Rear view.

Heaters in the dark.

I have two videos of the set singuing again, but by a fault in my smartphone I can't upload them.

 

[LW1DSE]

The original schematic. As it is designed for 110V, and here we have twice this voltage, I replaced the heater droping resistor with a 4uF capacitor, and the field coil is in series into the DC circuit, both sections of 25Z5 rectifier in parallel.

This is *my new* schematic. Some voltages measured in situ.

 

[Ham4CW]

It always amazes me how a bundle of wires and a tangle of components can produce such mellow sounds.

Nice restoration!

73, Mark...

 

[LW1DSE]

Many thanks, sincerely.