Emerson DS-436

© Copyright Alexander D. Schapira, 2014, All rights reserved

Here is an account of how I restored and repaired an Emerson DS-436 receiver.

I hope this will be of some interest to other Emerson afficionados.

Click on any picture for a larger view.

I acquired this radio at a yard sale some years ago. There are a number of very similar Emerson models sharing the same chassis including the DS-372 and DS-365. The cabinets differ slightly in their contour and trim.

Before investing too much time and effort in the radio, I checked that critical components were okay. The power transformer, IF cans and antenna and oscillator coils ohm'd out properly. The nine tubes, (2) 6K7, 6SA7, (2) 6SQ7, push-pull 6L6's, and 5Z3 rectifier tested normally. The 6U5 eye tube, which I cannot test, turned out to be very dim. It got replaced with a nice bright one.

As found.
As found.
The radio is unusual in that the speaker points up, through louvers in the top of the cabinet, and the chassis fits into the cabinet from the bottom, not from the back.
The radio had a thick wooden bottom 'plate' which I'm sure contributed to the severe overheating of many of the components. I did not re-use the wooden bottom plate; rather, in order to provide better air circulation, I fabricated a bottom shield from perforated sheet metal.
The cabinet was grungy and the decals were worn or missing.
The chassis and dial were very dirty, but topside everything was in tact. Below chassis it was a different story.
Several of the high wattage resistors were severely cracked as a result of over-heating.
This radio has a slide-rule dial for tuning as well as for volume and tone indication.
The dial strings run on wooden pulleys.
I replaced the electrolytics in the power supply, all wax capacitors, and all resistors.
The chassis cleaned up nicely. I also removed and cleaned the tuning capacitor.
I cleaned the dial and repainted the pointers.
I de-rusted the transformer shell, primed and repainted it.
Cabinet work.
Installation into the cabinet with new rubber grommets.
The broken glass behind the dial window was replaced with a new reproduction dial cover.
The Ingraham logo was put back onto the cabinet.
And decals were replaced.

Finally, I aligned the set according to the service instructions. Reception is excellent with the built-in antenna.

I added X1/Y2 RF bypass capacitors to the AC line, and a 15 ohm/12 watt series line resistor to reduce the transformer primary voltage by about 12 volts to about 110 VAC. The radio draws about .8 amp during normal listing. It sounds great with audio from the push-pull 6L6's.

It was very satisfying bringing this set back to life and restoring a radio of sentimental value to friends. I hope you enjoyed the story. Please feel free to contact me at w2ads@arrl.net

    -Al Schapira, W2ADS

Page last modified 11/09/2014