About This Restoration

This project documents the restoration of a vintage Silvertone AM-Shortwave radio. Silvertone was the house brand of Sears, Roebuck and Company, and their radios were among the most popular consumer electronics in America from the 1920s through the 1950s. While Sears did not manufacture the radios themselves, they contracted with established radio manufacturers to produce sets bearing the Silvertone name.

The Radio

This particular Silvertone model is a table-top AM and shortwave receiver housed in an Art Deco wooden cabinet. The shortwave capability allowed listeners to tune in stations from around the world, a feature that was especially popular during the 1930s and 1940s when international broadcasting was at its peak. Shortwave bands also carried time signals from stations like WWV, connecting this radio to the broader theme of time distribution that runs through this collection.

The Restoration Process

Restoring a vintage tube radio requires a methodical approach to ensure both functionality and safety:

Safety First -- Capacitor Replacement

The most critical step in any vintage radio restoration is replacing the old electrolytic and paper capacitors. These components deteriorate with age and can fail catastrophically, potentially damaging irreplaceable transformers or causing a fire. Every paper and electrolytic capacitor in this radio was replaced with modern equivalents of the correct value and voltage rating.

Resistor Inspection

Carbon composition resistors, the type used in most radios of this era, tend to drift upward in value over the decades. Each resistor was measured and compared to its marked value. Those that had drifted beyond 20% of their rated value were replaced.

Tube Testing

All vacuum tubes were tested for emission, shorts, and gas. Weak tubes were replaced with tested equivalents. The tube lineup in this radio is typical of the era, with separate tubes for RF amplification, local oscillator/mixer, IF amplification, detection/AVC, audio output, and rectification.

Cabinet Restoration

The wooden cabinet was cleaned, and minor veneer damage was repaired. The original finish was preserved where possible, with touch-ups applied only where needed to maintain the vintage appearance.

Alignment

After all component replacements were completed, the radio was aligned using a signal generator following the manufacturer's procedure. The IF transformers were peaked to the correct frequency, and the oscillator and RF tracking adjustments were set for proper dial calibration across both the AM and shortwave bands.

The Schematics

The original schematic diagrams for this radio are included in the gallery. These diagrams are invaluable for any restoration effort, showing the complete circuit with component values, tube pin connections, and alignment points.